All of the above recommendations are great, the best you can do limiting yourself to big box stores. I would recommend you try Crutchfield.com. Their prices are as good or better, their sales people really know what they're doing (versus seasonal high school kids), and their customer service is great if there is any need to return or for assistance with set up etc. They have some mid-fi stuff but are generally aimed at the mass consumer.
Good luck.
Good luck.