I don't think you need to personally mention that your links are referral links. This would be distracting to the message, and might even potentially scare someone away from microstock, thinking this is some gimmicky pyramid scheme. What internet savvy creative professional doesn't know how to read a common mouse-over link? Whenever you hover over a hyperlink you see the actual URL in the footer of your web browser.
If someone wants to learn how to market their photos, it's only fair that Thomas gets the credit for their referal. What good is it for them to just sign up without someone elses referral link? Why not help out Thomas, in return for him taking the time and effort to throw together such an informative site?
Having a bit at the beginning about how the following links are referral links is just distracting. I've never seen such a thing, even on homepages of some of the major players in stock like iophoto
iofoto or Yuri Arcurs
www.arcurs.com
I usually tell people verbally about the referral setup, especially if I'm chatting with them on forums or facebook. After answering their initial questions I request that if they sign up for any of these sites, to please follow the links from my website, in order for me to receive credit for referring them. They are usually more than pleased to do so in return, for the help and one-on-one personal advice that I've provided them with.