Braves, trust me on this one ... if your going to buy a receiver, make sure it can output HD audio this way your not buying another receiver again later on ... Onkyo's 605's and up do that.
ecost.com has them the cheapest.
as far as your tower speakers ... Polk Audio r50's you can get at frys for 59.99 each ... its the best bang for your buck hands down .. they are kinda bulky /big tho ... they are the ones you see in my HT. There is one Frys in Indiana. (frys.com)
if your looking to just get some small surround sound for your dorm room then I suggest a HTiB kinda like cali ... ofcourse with that option your throwing HD audio out the window.
For less than $400 you could have a 605 and 2 r50s ... the main thing is being patient and buying piece by piece ...