I've bought a lot of sex toys from Amazon.com. They have great price on a lot of products, and they have very good customer service. Warranties are valid with purchase on Amazon as well. I bought Ina for 70 dollars on amazon a few months ago with 2 days shipping.
I would buy toys from ebay, but only from trusted/authorized sellers. It's partly because I am very comfortable with buying/selling on ebay. Many people don't know that if you are not satisfied with your purchase on ebay, you can file a claim and get your money back easily.