I would just diligently peruse EAttorney a couple of times a week. You'll notice a bunch of random jobs seem to post right around the end of the semester for small firms. I wasn't selected for a single OCI, but still got a paid gig as the result of being diligent.
I've also heard you can find stuff on law crossing, but I've never used it.
If you're really desperate, you could always just call the local gov't and non-profits, and volunteer your services as a clerk...but, I think I would rather jump off a building and catch my eyelid on a rusty nail than clerk for free.