Syncing iTunes with Sugarsync

Question

Hello,
I'm hoping some advanced mac/itunes user would have an idea of how to accomplish my goal. 
Question: Is there a way to use sugarsync (or just in general the idea of a duplicate file system) to have an identical itunes experience on 2 macbook pros and a windows 7 desktop?
Explanation:  I have a windows 7 desktop and 2 newer Macbook Pro's.  All are consistently updated with the latest OS and iTunes updates.  In general, I'm trying to make it so that my media and files match as exactly as possible on each machine and they can be used interchangeably.  I have a highly organized and complex filing system with a large amount of files and have successfully been able to do this for everything so far except for music/iTunes.  I have about 80-90 gigs of music all organized in folders/subfolders within the iTunes music folder that originated on my desktop.  99% of the music I've ripped from CD's rather than purchasing or downloading through iTunes so, from my understanding, that makes iTunes match and home sharing not really an option.  What I want to do is use sugarsync like I have for the rest of my media/files to sync the content between the desktop and 2 macbooks so everything will be identical whenever I go between using one or the others.  For example, I want to be able to have my wife rip a CD into iTunes onto her Macbook at work and (after uploading time) be able to go and have it on my PC at home as well as any playlists that it's been added to.  Similarly, I want to be able to rip a CD or make a playlist from my home PC and go on either Macbook and have it automatically be the same when I open up iTunes.  I've tried doing the research and while sugarsync says it doesn't support this feature, it is so close to working.  I have it so that the files are all synced correctly and automatically and any changes made on one machine are automatically changed on the others. 
There is just one problem that I can't figure out and if I could get this right it would work perfectly.  The iTunes library file that originated from the desktop points to the media based on the PC file path c:\users\username\my music\itunes\.  On the mac it's users\username\music\itunes.  So even though I have everything syncing exactly within the main itunes folder, the library file points to the path on the PC.  So when I open iTunes on the macbooks, all of the music is there and all changes are made, but I get the exclamation points by each file, showing that iTunes can't find any of the media.  I haven't done this, but I would guess that if I direct the macbook to the correct folder to find all of the music, it will do so, but then give me the same problem on the PC where it says it can't find anything and cause me to have to keep redirecting every time I use iTunes. 
I'm hoping someone can give me any insight into a fix here because I have everything so close to being set up exactly how I want and this is the one thing I can't figure out.  I have two basic theories, but don't know if and how they're possible.  One would be to have sugarsync sync the media as I already have it, but have the macbooks have a separate library file from the windows desktop so that they can each point to the correct file path.  The other is to somehow have the iTunes software on the macbooks point to the correct file path in a way that doesn't rely on or alter the library file so that it will automatically know where to locate the files. 
Does anyone have any experience or insight into this or have any other suggestions?  If your suggestion is to buy a mac desktop, I'd love to, but have to finish paying off the macbooks first.
Thanks

Answer 1

"Are my movies, etc, now on the hard drive of the apple TV?" when user syncs the files are on the ATV hard drive up to a finite capacity. If user deletes any of the files from the itunes library used to sync then they get removed off ATV hard drive.
"close my MacBook" streaming does not work when the computer is sleeping. Requirement is computer on and itunes open to stream. Should not effect synced files though.