It seems to get the rebate you purchase one of the starter kits with the tmf peelie affixed and then go to the website glade.com/oildiffuserrebate to print a form. The rebate includes the cost of the unit, less any sales tax paid.
Well, if you hop over here first, you can print a coupon for $2 off these making for a small money maker even after tax and cost of stamp to mail :D I can't wait to try this out!
You should also be able to find these specially marked packages at HEB (my mom did!)
Don't understand my lingo? Go here.