You could start by contacting the USCF clubs in your area. They might know of other tournaments not heavily advertised.
http://www.uschess.org/component/option,com_wrapper/Itemid,198/
The bad news is that almost all USCF tournaments expect you to bring your own equipment. Depending on how kind the organizer is and how bad he wants more players, he might be able to arrange a loaner set. (It's just easier to buy an inexpensive set so you don't have this problem.)
How do I find a tournament near where I live, preferably where people without their own set and clock can play? I've never been to an OTB tourney, but I would like to do so over this break before school starts again.