How to sync my iPhone with more than one computer?

My computer has all of my downloaded music, but it's too small and doesn't have a CD adapter, so I have to use a different one for my CD's. I just got an iPhone and it says I can't sync it to more than one computer without deleting everything. This is exactly what I used to do with my iPod and it worked just fine, and this is pissing me off cos I want all of my music but it won't let me.

Itunes.

You can't you can only sync on one computer

But I wonder why not sync your music to iTunes?

You have to have both computers use the exact same database. You can copy this from one computer to another. There are instructions on how online. This is possible hard to maintain.

Another way depends on how portable the computers are. You can have it use a NAS or other external drive for its database.

As for reading a CD's in a computer that doesn't have a CD player, that can be easy. On the computer that has the CD drive, share it. On the computer that doesn't have it, map the shared CD drive. Then you can use it like it is local. You can also put the resulting files on the network somewhere and use iTunes features to make them local.

Oh, and you should probably backup that itunes database somewhere anyway, in case the computer breaks.

As for the too small computer, Get another drive that is bigger. If you have no drive space in computer, you can get one of these http://www.compusa.com/applications/SearchTools/item-details.asp?EdpNo=2477926&CatId=3770 It will allow copying existing partition to new drive. Then you can expand the space and have room again.