How nice to make the effort to recommend your agent! You can either ask your agent what sites you can find him/her on the web and its easy to make a recommendation there. I also think it would be a a good gesture to send a hand written note to the manager/broker. Real estate agents work very hard and always appreciated to be recommended.
Go on twitter and tweet something about how impressed you are with what they did for you...maybe do a search first to narrow your tweet in a spot where people are expressing frustration on the issue of home buying or selling...whatever the topic is that your agent impressed you with. And, you can write a review for them here on Trulia!
Tom Hinz http://www.shortsaletosell.com