I know that phish is coming June 23 and 24...and its at deer creek, er, i mean verizon wireless(sounds so lame)
i, too, am unlucky enough to reside in indiana... as of yet, i dont know of any festivals... as someone said, phish is coming, and i think the dead are, sometime... but that's all i've heard of so far.
check out jambase.com festival guide. Phish Deer Creek is the only show I know of though. But there may be some not too far away.
hippy hill hoodang is the end of august at bean blossom there seem to be more in OH and IL http://hippyhillhoodang.com/details.shtml
there's plenty of good fests in Ohio...Gratefulfest (nlqp.com), Ripplefest (bluffton, OH), and there's always hookahville on memorial day weekend and labor day weekend. All of these are worth checking out