Maz,
I can't talk about Balfa camp but I have been a visitor to the area and I agree with Nick that you absolutely will need a car. And you will love having it because there is so much to see that is within a short drive! You can easily visit Eunice, Church Point, Mamou, Opelousas etc. etc. Festival International is wonderful, especially the LA Folks Roots workshops. I don't know how it will be for your, but it was cheaper and easier for me to fly into N.O. and drive a rented car to Lafayette than it was to fly directly to Lafayette, go figure. (Of course that was before Katrina.)
My main reason for writing is to urge you to get ahold of Macon Fry & Julius Posner's CAJUN COUNTRY GUIDE it's chock full of information about places you will want to visit--it's indispensible!!! And take the time to visit historic places like El-Sido's in Lafayette, and Marc Savoy's Saturday jam sessions. Go on a tour of Lake Martin--it will be nesting season then.
There's a tiny town, Arnaudville, which has a little etouffee fest the same weekend as Festival International. I went there last year and saw Geno Delafose--now that was an experience I will never forget. You will want to check out a free weekly paper "Times of Acadiana" (I think?) for listing of clubs etc. Whatever you do, Maz, I know you are going to have a wonderful time! I'm just a visitor, and I'm looking forward to reading suggestions from the locals.

Thanks to all for your input. Anymore input is still welcome. I am taking note of the Guide and Paper that Claude was referring to. There is indeed a lot to see and do, and as I will only be there for about a week, I am planning on going back afterwards.
I am really hoping to have time to do a little bit of driving around and visit Eunice and Iota (Savoy & Miller) among other interesting spots.
Cheers... Maz