Upload & Sell: On
John Harrington's book "Best Business Practices for Photographers" will have something. What you are looking for is called a licensing agreement. Maybe that will help your search.
I just write an itemization listing the term, media type (magazine, web, brochure, etc), term (one year, one month, in perpetuity) whether it's exclusive, and the positioning in the media (front page, run of publication, etc). I always state that I retain the copyright and restrict the clients ability to redistribute for any purpose.
No legalese, just plain English.