Hi Rod,
I've just answered a similar question a couple of minutes ago on the Warriors Forum. Here's my answer:
I use and recommend (no affiliation whatsoever) Freedback (
http://www.freedback.com).
It solved most of my support form problems at
http://www.silverlotto.com/support.htm and has run solidly and reliably for a couple of years now without any bugs or fixes. It sends both emails back and to the client, and you don’t do any HTML. There's no CAPTCHA, but you could put a filter in your mailbox to solve any spam problems like that.
I've tried quite a few HTML alternatives over the years until I gave up (forms are notoriously buggy) and went the automatic route. Freedback solved my problem.
Ken Silver