Sorry, but it is not "you". There is gonna be nothing that "you" can purchase to make it work, unless you want to make a donation to the school and setup your dorm buddies. "Your" computer is good to go (most likely) but the school has not set up a wireless network to service the dorm(s). They would need a hub and wireless stations situateed throughout the building (and people to service and maintain them) - and they are most likely not planning to do so.

I don't know why, but most schools are setup this way. They have wireless capabilities at various locals throughout the campus, but "not in the dorms".