You can buy songs from walmart.com that say they are compatible with itunes and use itunes for that. But I'm pretty sure you must use itunes with any ipod. You can also import songs you already have on CD into itunes as well. As long as they are in mp3 format you should be able to use itunes with songs bought elsewhere. Also itunes sells workout mixes at a less $$ price when you buy the whole collection, that might be an idea if you just need a good beat and aren't super picky about specific songs.
M, mommy to A 2005, E 2007, and L 2010