Congrats!! We have a lot of E36 owners here, feel free to hang out with us and ask questions. You won't get the "don't ask, search the forums" attitude that some other boards give you.
I have two E36s both at 150K miles. These cars are good for 200K miles and more if taken care of. As mentioned, the cooling system generally is the weakest link, as on most cars.
You can drive it as is, or do some upgrades. At this age, the various rubber bushings start to dry out and the car feels a little loose or sloppy handling. Replacing bushings will bring it back to top performance. With the exception of the front control arm bushings, none of these are critical. The front control arm bushings can seriously reduce the steering accuracy to the point of being dangerous, and should be replaced if they get bad.