To be honest, I've pretty much given up on tracking rebates in real time because they now come and go so fast, and when they go they're back again (often right away) sometimes with slightly different prices or different deals (e.g. camera and lens combinations, multiple lens purchases, camera lens and printer combinations). Keeping the list current would now be a full time job!
The best way to find current rebates is to visit a retailer who lists them! They're paid to keep the list current so I let them do the work for me so I can work on other parts of the website. The retailer lists are good because you know exactly what's on offer, what's in stock and exactly what price you will pay. So here are some direct links to lists of current rebates:
The expired rebates used to be listed on this page but in order to speed up page loading, I've moved them to their own page: