It may be that your question may need a little more detail added so that we know what you have and what you are trying to do. What kind of heat do you have? Electric? Hot water baseboards? What are you trying to accomplish with these diffusers? What is the problem that needs solving. I would wager that the lack of response has more to do with your economy of words than with any drought of ideas or suggestions from the kind contributors on the board...
BTW, I got 143 responses to a search on Google.com http://www.google.com/search?q=baseboard+heat+deflector and some of the links looked promising...
More time typing details and less time re-posting will usually produce good results on this board :)