Buy it at a place like Best Buy with the extended warranty. If it breaks for any reason, they just give you a new one off the shelf. No shipping it in or any bullshit like that. My roommate has the Best Buy 3 year replacement warranty, so he gets a new iPod everytime they come out with a new generation by just throwing his iPod at the wall and cracking the screen. Best Buy will replace it no questions asked, even if it is your fault.
My experience with iPods has been really negative. I've had 2 iPods who had harddrive malfuctions in 2 years, only one of which was successfully warrantied through apple. I can't afford to replace it now, so I'm stuck without one. Although the user interface is pretty nice/fun to use, iPods a generally pieces of shit. So many of my friends have had the same harddrive issues I have, and apple doesn't really give a shit. They know you'll keep comming back for more, so why make it better quality?