I have a fundamental problem with buying clothes off of ebay. For the better brands (Diesel, True Religion, Paper Denim), each pair of jeans is slightly different and needs to be tried on.
As far as where to buy these, try larger department stores like Bloomingdales, Hechts, Nieman Marcus, and Nordstroms. Diesel has stores and they have everything there. So Does Energie (although it's the Miss Sixty store).
Also try vintage stores, they usually have some great jeans that are already worn. God, I love clothes. And I'm straight. I swear.