Originally Posted by
FFMilesJunkie
Apple now allows you to re-download all previously purchased iTunes music. You just need to download the latest version of iTunes on your new computer (v10.3).
My recollection is that you can "authorize" a limited number of computers (I think 5), so if you are under that limit, this should work as your first step.
Originally Posted by
thomas199023
I imagine you can just copy the MP3 files or WMA or any other format to your android phone.
Purchased content is in .m4a format, which AFAIK is not directly playable on non-Apple devices. I don't think Apple provides any way to migrate them to a another format directly, there are probably third party tools to break the digital rights management, and convert them.
Itunes also allows you to create music CDs, so you could write to CD (or disk image, maybe), then rip back to MP3 outside of Itunes. If you have a large library, that could be time consuming.