I think this would be cool too. It'd also be cool if we could get email notifications when favorited requesters post new HITs.
In the hits page type the requester name and click on go button. After finding the requester Just click on the requesters name then you will be able to see the more hits posted by that particular requester.
Well as far as I can make out, go to the hits page as normal. If you see a requester that you like doing work for click on their name (on the list its on the left hand side of the page) and if they have put any other jobs on then they will come up on the list. However I cannot see a search box that will bring up the requesters work, the normal box labeled 'containing' doesnt work that way.
The trick is this: when you have found all the HITs of that requester bookmark that page! Save it to your favourites and now every time you click on that bookmark it will start an internal search and bring up all the HITs this requester has up right now.