How do I start iTunes with whichever iTunes library I want?

Question

How do I start iTunes with whichever iTunes library I want?
I've created a 2nd iTunes library using the "press shift-key while opening iTunes from the start menu" method given in iTunes help. Now, when I try to start iTunes from the Quick Launch menu or from the system start menu, I get the new library--without choosing it.
Otherwise, the new library works as I'd hoped. By turning off "Copy files to iTunes Media folder when adding to library," I'm able to use "Add Folder to Library" (where the folders are in the 1st iTunes library) without using more disk space for the 2nd library. So far, it works just fine for CDs and movies. I'm anticipating an iPad which can hold much less than my iPod Classic.
I have the latest iTunes (10.2.1.1)

Answer 1

A solution found!
I found where Apple addresses the question. Actually, I had tried this before I found Apple's answer and before I asked the question here and I didn't get it to work. I finally have it working, but the Apple answer is missing a step--or so it seems.
Locating Apple's answer:
From the iTunes window,
Help > More resources > iTunes Support Website > iTunes Library and Backup > iTunes Library >
How to open an alternate iTunes Library file or create a new one.
Apple quote:
1.If iTunes is running, quit iTunes.
2.If you are using Windows, hold down the Shift key and from the Start menu and choose All Programs > iTunes > iTunes.
3.If you are using the Mac, open iTunes and immediately hold down the Option key.
4.You should see one of the following screens:
End quote.
As it says, you get a prompt to: Quit or Choose Library or Create Library.
I created my new library by choosing "Create Library" and expected to be able to use "Choose Library" later. So, when I clicked "Choose Library," I got a new window that's titled "Open iTunes Library" (it looks a lot like a Windows Explorer window). I selected (on the sidebar) the old library, clicked "Open" and nothing happened. The problem is likely my inexperience with this type of issue, but, still, the solution seems hokey.
After too much screwing around and a 24oz beer, this is what's working:
1. If iTunes is running, quit iTunes.
2. Hold down the Shift key and from the Start menu, choose All Programs > iTunes > iTunes. (You don't have to have the shift key down until just before you click the last "iTunes.") Don't release the shift key 'til the prompt comes up.
3. The prompt is: Quit or Choose Library or Create Library. Click "Choose Library."
4. When the "Open iTunes Library" window comes up, click the desired iTunes library on the sidebar. (Mine are named "iTunes" and "iTunesIPad.")
5. Then, you'll see a list of items in the right pane. Find the file named "iTunes Library.itl" and click it.
6. Now, with both the iTunes library name selected on the sidebar and the "iTunes Library.itl" file selected in the right pane, click the "Open" button.
7. iTunes will come up using the desired library.
8. Using iTunes from the Quick Launch menu or the desktop will bring up the same iTunes library again, even if you shut down your computer.
9. When you want to change the iTunes library in use, start at step 1.
Nice about this, is that I would only have to get into the "iTunesIPad" library if I need to add something to it from my regular "iTunes" library or I want to sync to the iPad. Most of the time, I'll use my regular 185GB "iTunes" library (even here, I deselect many movies so that I can sync the library to my iPod).
Caution:
I must add the warning that I'm doing this because the iPad (that I don't have yet), won't hold even half of what I have in my iTunes library. At this point, the "iTunesIPad" library will take up very minimal disk space since it's using pointers to the regular library rather than copies from the regular library AND it's easy to switch between libraries only when needed. I can't say that this will all work until I try more setup work and I actually use it with an iPad. If someone knows that this is going to cause problems or if they have a better idea, I'd sure welcome comment. BTW, before trying this, I restructured my iTunes library (File > Library > Organize Library > Reorganize files in the folder "iTunes Media.") to bring it up to date and then backed it up on an external drive. The website "iLounge" has an article about the old and new library structure.