When you say much too thick? What are your thoughts on this? As Gilmer wood and many others offer backs , sides and tops that are within limits of acoustic build specs. So please give us more info on your requirements and who it is that you are referring to that don't offer this. Now if you are looking at Billets and want to resaw or split your own, then that's different. some more info will help to answer the question.
MK
The company I'm looking at sells the wood in board feet. 12x12x1 is 1 board foot, some wood is available in 2 inch thicknesses, so it's 2 board feet. Of course, 1 or 2 inches is way too thick for acoustic guitars. I'm no experienced with carpentry, so is there a tool/table that will plane wood to re-adjust it's thickness? I'm assuming acoustic soundbards and backs and sides are 1/8-2/8 inches thick, am I not correct? So, that's my target thickness.