Man, all of you MTSU girls! Must be a good Greek system because you girls seem to be beating down the sorority houses doors!
It's also nice to see so many non-traditional students rushing there. Welcome to GC, devoted04!
I would do a search for you, but I think you can simply get a lot of information from two resources:
1. Two other girls are going to be going through Formal Recruitment there also. MTSUgurl is one of them... she sticks out because of her ID and the fact that she is a regular here!
2. Read through the first page of threads. It may seem overwhelming, but you do have a month to do it.
Sorority costs depend on the chapter itself and many other factors. Please keep in mind that, for the most part, ALL of your costs are included, and include (inter)national membership dues (which are usually not much more than $50/year). Sometimes living expenses are also included.
As for dress... well that's been the hot topic lately! I'd talk to one of the girls at your school or see if they offer a Recruitment catalog there. Sundresses seem to be rather popular at this point in time, so you won't have to get a new Prom dress or anything, but just make sure you look nice... no need to try to be Barbie!
Whew, I hope that helped.