I agree, if you are even somewhat interested in biking, you need to go to a dedicated bike shop.
The bikes you find at the mass marketers are basically junk. They're cheap, with cheap components, and meant to appeal to the "lowest common denominator."
Go to a real bike shop and you'll find a world of difference. Yes, you'll pay more for your bike, but over time, the extra $$$ you invest up front will pay dividends down the road. It's absolutely worth the higher initial cost to buy a quality bike from a dealer who carries a nice selection of quality brands–and the knowledge and expertise of the staff at a bike shop are something you can't get at a "department store."