Web4future has a nice free, "form2mail" script.
Karlcore.com sells a simple but very effective contact form script for $4.95, lalong with an assortment of other simple scripts, such as a Links manager, a mailing list manager, and a simple PHP secure login manager script.
www.resourceindex.comÃ‚Â has scripts of all kinds, many for free.
www.hotscripts.comÃ‚Â is also an excellent directory for all types of scripts, whether free, shareware, or paid.
Matt's Script Archive is the original home of Matt's Formmail Script and many others.