This could be done by running an automated script that makes an e-mail address temporarily adds it to your site. Then another script that check's said e-mail address.
This is a problem with e-mail spam, but I think hiding your real e-mail from spambots is the main concern in this if I am understanding you right.
However these are designed around obscuring MY email address, and using 10minutemail.com or 33mail.com's domains.
I need to create emails for my customers that will forward to THEIR email addresses when another party contacts them, preferably using my own domain.
While I guess I technically could figure out a way to use something like 10minutemail and register accounts for all of the users of my site, it would probably require:
1. the users of my site to tell 10minutemail that it's ok to forward to them (during 10minutemail's registration process)
2. i would have to post 10minutemail.com domains as the contact info for the customers of my site, which is an undesirable UI.
If I'm missing something and I can in fact use existing services to do what I want, please fill me in, because I want this, I just don't want to build it (yet, anyways).
craigslist implements something like this now. If you email a CL anonymized email address and email back and forth, you never get the counterparty's email address.
Basically craigslist just acts as a relay, so all communication actually happens between $PERSON_A and Craigslist and separately between $PERSON_B and Craigslist.