From August till now, I've purchased 3 mp4 players between these two sites:
www.campus111.com and
www.pigpony.com.
They have really good prices in my opinion and are also found on eBay under the ids campus111 and pig-pony. The first mp4 I bought was a 1.5" with double speakers and double headphones in 512mb for $31.95 plus $9.95 shipping, the second was the same except 1gb for $37.95 plus $9.95 shipping, and the 3rd was 1.8" for $33.95 with free shipping (must have been a mistake on their part because no other product had free shipping). However, I ordered it the 3rd of October and still have not received it! They said it got lost in the mail or something and that they were out of stock on it so they couldn't reship another one, so I'm going through with a refund and will hopefully try my luck elsewhere. I think my particular situation in not receiving the mp4 player was abnormal so I'm not going to bash them because of it. They have really good communication and are located in the U.S.