While the iPod is a good player but it tied to iTunes which is a massive, incomprehensible and control-freak ball and chain on users.
Other players will operate with PC or Mac like an external drive to which you simply drag and drop music files. Sony's small flat players which resemble the last iPod Nano are typical -- and I like the sound, logical controls and battery life. And if you shop around they're cheaper than Apple equivalents -- my 4gig model was last on offer at $60 or so and has a bright colour screen, FM radio and shows pix and (allegedly) movies.
Once music is on a Sony, unlike an iPod, there is nothing to stop you connecting your player to friends' computers and adding files or swapping them.
You may have some fun trying to move your current iTunes music collection to any new player (including a new iPod) unless you have operated iTunes in a logical manner and maintained folders for each album (which is unlikely as few Mac owners seem to understand that a computer is essentially a filing system) but there is help available.
I lost my iPod and do not feel like paying $250 for a new one. I have a Mac however, and am not sure which other brands are compatible. I maybe only need 16GBs. Any recommendations?