Hi there. Based on what I've seen around here, that doesn't sound like a terribly bad deal. I've seen the M3s with similar mileage for about $23-$25.
What exactly are you looking for with the car? You can pick up an earlier 325is for about $10K (half the cost), but then you don't get the added M3 performance. Either way, the E36 chassis cars are a great way to go.
Also check
www.recylcer.com for a listing of current prices on M3s here in SoCal. This will give you a good idea of what to expect and what to pay...
-Wayne