Using the same itunes account for two users on the same macbook pro

Question

Hi all.  I purchased a macbook pro in september (which I have absolutely adore), but because my semester was so jam packed with work, I wasn't able to take it in for my data transfer until the Christmas season.  Everything was transferred correctly, but for some reason the transfer leaves me with two different users on the same macbook.  I don't really have any problem with this, except I want to access the music from the "old user" with the new user that I have been using since I purchased the macbook.  Is there any way that I can move my music from one user to another?  Bear in mind that I only have one itunes account, and almost all of this music was purchased legally through itunes (I had some old cd's that I transferred back when I first bought the original macbook back in 07).  Thank you!

Answer 1

I'm assuming that you want to get both your purchased music AND your ripped CD's back into the New iTunes Library.  If you use iCloud to re-download all your purchased music, TV, apps and books you wont get your CD's or movies back; and you'll use up a lot of internet bandwidth and time to re-download everything.  So, I'm going to give you a way to get the music and everything else off the hard drive into your new iTunes Library.
But, I need some clarification here.  I'm assuming that you recently used Migration Assistant to move your old Mac's user account to the new Mac, so when you turn on the new Mac you have a choice to log in as either the "Old_User" or the "New_User", or something like that.  And both user acounts are using the same iTunes music store Apple ID, right?
And, I'm assuming that you have both accounts set up with your iCloud or MobileMe information, so they have the same info in the contacts, calandars, bookmarks, and notes.  If you didn't use iCloud to load this info to the new user, then importing your old contacts, calendars, bookmarks and such will require an extra few steps, and is a different process entirely (composed of exporting the data from each of those apps while logged in as the Old User, and then importing them while logged in as the New User). 
I'm assuming that the main differences in the two accounts will be that your old documents, old downloads, old email, old iPhoto and old iTunes library are not merged with the new ones, right? Apples Migration Assistant would have merged the Mac Apps folder and copied over all the Shared Users documents if it was done right. I'm also assuming that you kept your old iTunes Library in your Old User account and not in the Shared Users folder, right?
If that's the case, first decide which account will become the primary account that you you will use all the time from this point forward.  You may want to choose the account that has the most recent work that you have done with the computer over the past semester since it's set up the way you like it, or the account that has the largest amount of data and history that you don't want to move.  The next step will be done by first logging into whichever account you wont be using in the future (except to access old info that can't be moved).
If you are happy with how it's working now and just want to move your old documents, photos, and music over to the new account, then it seems to me that it would help things if you first log in as your "Old User" name" and move (or copy) your old documents, downloads, iPhoto Library, and iTunes library to the Shared Users folder. 
I would basically move everything important in the Old User's home folder to the Shared Users folder, keeping the files in the proper subfolders like "Music" "iTunes" "Pictures" "Movies" "Documents" "Downloads" etc...  However, if your New iTunes Library or New iPhoto Library and such are already in the Shared User's folder, make sure you don't replace them with the old ones, by renaming the old ones first (maybe add the word "old" to the name.
Mind you, when you have moved everything, and you log out of the Old User acount, and then log in as the New User, you will usually have to enter any administrator's User name and password whenever you want to make changes to those old documents while logged in as the New User.  Before going forward you should first change the User Permissions of those files to let the New User "own" them, so it will stop asking you for a name and password every time you want to access them in the future. 
EVERYTHING from this point forward assumes that you are now logged in as the New User, and you should not ever need to log in as the Old User, except to access your old email archives or old Keychain Access to find stored passwords (which I think are stored in the Old User's "Library" folder which is invisible and inaccessable in Lion).  I don't know how to merge old saved emails or keychain passwords into the new account (mobile me can sync the keychains or mail rules/accounts, but iCloud can't, and mobile me doesn't sync the actual emails that were downloaded since 2007).
First, to change the "Sharing & Permissions" to the New User just select "Get Info" for any old document or enclosing folder that need their permissions changed to the New User, click on the little lock icon at the bottom right of the Get Info Window, authenticate with any Administrator's Name and Password, and click okay.  If it shows your New User name as "Read Only" change that to "Read and Write".  If your New User name is not in the list, click the "+" icon on the bottom left and select the New User name, and set it for Read and Write.  Sometimes you have to do this "+" user step more than once to get it to stick. 
Then, after your New User name shows it's set for "Read & Write", with your New User name still selected, click on the little "cog-wheel" icon next to the +/- buttons, and choose "Apply to Enclosed Items".  The computer could take a long while to finish changing the permissions if there are a lot of files in the folder you changed, so be patient.  When it's done you should "own" all the files in that old folder as the new user.  You are now ready to proceed with importing the old music into the New iTunes library.
First launch iTunes (still as the New User), and go to File > Preferences > Advanced.  Make sure iTunes is set to "keep itunes media folder organized" and "copy filkes to itunes media folder".  Click okay.  It may open a small window showing that things are being moved and organized, with a progress bar, and then it's done.  It wont do that if you are already organized and copied. 
At this point, you could simply locate your old iTunes music folder in the Finder and drag the Finder folder onto the open iTunes app window and let go of the trackpad button when the cursor changes to a green "+" sign, and it will import and copy everything into the new iTunes Library.  When it's done you can delete the old Music folder in the Finder (not in iTunes).  However, you may not have enough hard drive space to make the copies, and it will be much slower than if you move the files in the finder before you import them.  You may still have duplicates of your ripped music that you added to the new iTunes Library, and can delete those from within iTunes.
My step to get the old music to show up in the New iTunes Library by moving them instead of copying them will be done in a particular way, that will avoid having the entire old music folder left behind to take up space on your hard drive, and it will make the import process significantly faster.  You are basically going to use the Finder to move the old music folder into the New iTunes Media folder, but you need to do it in such a ways as to not overwrite the new stuff.
So, before you move your old iTunes Music folder into the new iTunes media folder, rename the old Music folder with the word "old" in it, then move that folder into your current iTunes Media folder.  Move it, don't copy it.  If the Mac forces you to copy it, once it's done you can delete the old music's original folder, after you confirm it's all there in the copied folder.  This sometimes happens when you move files from Shared Users that you haven't changed the ownership properly before the move.  Now when you drag the old music folder onto the iTunes App window, since the files are already in the iTunes Media Folder it will not copy the files but will simply move them around and organize them inside the new iTunes Music folder.
You can repeat these steps with the old Movies, TV shows, Apps and Books, or whatever you want to move to the new iTunes Music Library.
I don't know how to "merge" the old iPhoto Library with the new one, but when you click on iPhoto in the dock while holding down the option key while you click, it will let you choose which iPhoto Library to open.  From a dialog box you can choose the old one, which you copied to the Shared Users folder earlier.  It's possible that a similar technique of dragging the old iPhoto library older on top of the iPhoto App window would import things, but you'd need to research that first.
I wish I had more time to proof-read this answer, but I have to go to a meeting, but can check back later for questions.