Who is your cable provider? I would call them and check to see if they provide internet serice. Most of them do. With some them, you can go to a store like Best Buy and get signed up and get a self install kit including a cable modem, splitter and cables. Are you going to use more than one computer? If you do you will need a router if the modem you get does have any routing capablity.
I just moved into an apartment and I have a cable hook-up. How can I hook that to my computer so I can get internet?
Call the cable provider. They will charge you a monthly fee for access and provide you with a cable modem. The building may have an exclusive cable provider and you'll need to find out who it is.