To summarize what everyone said, go to a bike shop and tell them you are a first timer and your budget. They will help you find a bike and let you test ride a few. If the shop has a few locations, they can call around a find the right frame size. My understanding is bikes don't have much of a markup, so it's hard to find sales. When they do go on sale, it would be the end of the summer.

I also love my Trek, but my DH made me try others and it concreted my decision.