I've got the same issue with my daughters 95 Contour and from the reading I've done it seems we are both headed for replacing the lock. You might try WD-40, it didn't help in my case, but is recommended by others on this site.
One other thing, we also found that it became difficult getting the key out too. The trick was this, shut the ignition off, then slowly turn the key back towards start, but not so far that you start the car, you'll hit a point where the key will slip out. Then remove the key, reinsert the TIP of the key only and turn the lock back. This will result in the engine and power off and the key out.
I'm, a newbie and this is from my experience only, I have no special knowledge.