Great! I started a group in college as well. It is a lot of work, and it is a lot of fun. :)
Start a blog for your group and direct people to it. It is the quickest way of getting a web page and it cost the least amount of money.
Also, be ready to do everything. And don't get dishearten if people promise to do things and then don't. Expect that. Instead enjoy it when people actually come through.
Also, find some project that requires a lot of people to do. If you don't have something concrete to give to people, no one will participate. Even if all what you do is have a cards night, that is good enough.
Ah, and always, always, always bring food and drinks, and advertise that. That will bring people together. Food is the oil for the social machine
If you need any advice, not hesitate to ask me.