How to notify a vendor object of a review?

Please is there a way to implement or hack a module in order to notify a supplier/vendor object of a review posted by users?
I have at http://webuyonline.org a review site about online vendors where users submit their reviews. I would like to be able to automatically notify the vendor one time and one time only that he was reviewed in order to invite him to the discussion.

I am using a custom form where users fill the vendor url address.
Is there a way to manipulate that field in order to change http:// (http://www) with "sales@" and then send to this address an email with pre-defined default content?
Thanks in advance to all the brains.