I agree with WYSIWYG that it's not near enough time for the scale of operation. HOWEVER, since you have organized this type of event, I am assuming in the same community, you probably have an infrastructure. That should help shorten the time required. You already have PART of the volunteer team you need. You should know the MEDIA (they will be very important in EARLY spring). Mainly you need VENDORS and VENUE and DONATIONS from SPONSORS.

Essentially I agree with MOST of what Conrad put together. I DISAGREE with #9. DON'T sell! Except for your own festival memorabilia, if you have some (T-shirts, ball-caps, or Artist CDs, etc). Let the VENDORs do the selling of product such as food. Otherwise you have to supply refrigeration/iceboxes, get cooks, cooking equipment, etc. IF you DO want to sell something(in addition to what I said earlier), sell water! People will want it.

I agree with Jerry. Hospitality for the performers and entourage is important. Someplace that IS inaccessible to average festival-goer. Even the friendliest of performers needs some time away from the "masses".