I bought a 325e two months back for 600 and a full tank of gas.
Had a oil pan gasket leak and battery was dying.
So far changed out spark plugs, new brakes+rotors, engine + tranny mounts, new oil pan gasket, new valve cover gasket, valve adjustment.
Still need to do short shifter kit and timing belt + water pump.
Great car and gets great gas mileage.
Also, you want a hardtop, softtops e30s make terrible track cars. Get a coupe and put the sway bar from a vert in, it will improve the handling ten fold.
http://www.r3vlimited.com/board/index.php