Ipod 4th and 5th generation

There is no 5G iPod Touch. The latest model is the 4G iPod Touch. This past September, Apple released a white version, but it contains the same exact hardware.

And yes, you'll be able to sync the device to your iTunes library without any issues. There is no limit to the number of iPods, iPads, or iPhones you can sync to one computer, iTunes library, or account.

B-rock

iPod nanos I'm guessing

Here

http://support.apple.com/kb/HT3845

You can determine the model via the information on this web page:

http://support.apple.com/kb/HT1353

You can then see a summary comparison of all the feature changes over the models here:

http://en.wikipedia.org/wiki/Ipod_touch

Regards.