I would also suspect a bad Idle Air Control Valve (IACV) and/or bad hoses between the PCV valve on the intake manifold and the camshaft cover. Also maybe a sticking throttle valve - due to a buildup of crud inside the intake manifold.
If you do a google search for "+neon +engine", and select the 'images' search instead of the 'web' search, you will get some pictures of typical Neon engines, some of which will allow you to link over to a Neon forum.
I bought a mopar manual for our 97 Neon on ebay that paid for itself in the first weekend. (Later I removed and replaced the motor, so even more savings due to that manual).
You havent said if your Neon is a single overhead cam or a double - but they are fairly similar.
I replaced the IACV in ours because it was letting the car die when the throttle was shut. The car had about 130,000 miles on it. I removed the whole throttle body to replace it, and even then it was hard to get the little bolts to loosen, and replaced the TPS at the same time - just for the peace of mind. I used plenty of penetrating oil.