Search on eBay because there is a ton of people that are selling their used iPod's this time of year because of the new ones coming out next year. Also craigslist is a very good site to pick up deals on iPods.
warranty, look like new. same for iMacs. I paid 994 for a 1499 iMac for my daughter, and just got the 8gb iPod touch for 149.00. true, might save a lot more on eBay and the like, but I hate flipping that coin and occasionally showing tails.
I bought a 16gb 2nd gen ipod touch brand new in Oct after I found out there was no new 3rd gen 16gb touch, My cost, 190 + free shipping, I sold it this month in Aug for 180 on Craigslist-before the new 4th gen iPod touch came out, So my total cost for a year of useage 10 dollars.
Hands down apple store, they replace any defective components, put it in a new case, ran through the same testing as a brand new one to make sure it performs to standard, plus comes with the standard 1 year warranty.
Buying anywhere else..you get what you pay for. Sometimes amazon can have some good used iPod deals.