Is there any relatively cheap ticketing systems or even free scripts for one?

The best free one I know of is called wreq, here is the homepage (http://www.math.duke.edu/~yu/wreq/).

Ticketsmith is free. Check out my thread that asked the same questions:

http://www.webhostingtalk.com/showthread.php?threadid=10852

If you do not mind running something that works on winnt server then there is a free package called liberum help desk
url is http://www.liberum.org/

Check it out. it is worth a look

Regards
Manish