Hi kevinmyles..
I have read your job description carefully.
You want to add free anonymizer as a services for your guest.
I have experiences build such web, so actually i can do this job in just few hours, depending your requirement. If you already have design and just load this anonymizer as a modul, I believe can do this quickly.
I can give you demo link if you wish :) or you can send me link/url your current website so i can "take" your design and setup this anonymizer script like real.
I'm new on GAF but i'm expert on PHP, XML, webservices, semantic web and have experiences for more than 2 years..
regards, wongkediridotcom