I did receive a letter, which basically said they'd love to admit me, but right now they can't, hence the wait list. It also said that if I need to remove myself from the wait list, or provide an updated address or phone number to let them know. Otherwise, I could hear from them anytime between mid-April or late-August.
Okay. In that case, the most appropriate step for you to take is to send a letter of continued interest. Basically, this is a letter stating why this school is your first choice (and make sure that the reasons are not only heavily researched, but also speak to more than just rankings, school offerings, or the location of the school--get deeper and more personal than that). Outside of that, you should stick to just exactly what they asked you to do: Address and phone number updates (if any). And then just sit tight and wait for an answer. If you take an offer from another school, let them know out of courtesy, so that someone else can potentially get your spot on the waitlist (or get bumped up to an acceptance).
A few outside resources that can help you:
http://blog.powerscore.com/lsat/i-was-waitlisted-now-what/http://www.powerscore.com/lsat/admissions/content_faq.cfm#23Let me know if you have any additional questions! I'm glad to help.