Thanks all for the responses. I got it done and it went like this: one guy, (young A/V guy, sole proprietor I think, randomly called from Craigslist), $90 first hour, $60/hr thereafter, 5hrs (!) = $330, plus cost of wall plates, speaker wire, etc - total came to $440. Oh, and that included hooking up HDMI to my mid-ceiling projector.
It would have taken me forever to do it and I would have put my foot through the ceiling, although I would have paid ~$3 apiece for the wall terminal plates from Monoprice instead of $15 apiece from Lowe's.
At the end of the day, I'm happy it's done, and the cost wasn't prohibitive.