Here we list some sites that might interest you:
It has tons of info, probably the most comprehensive propolis site in English language
www.facebook.com/groups/apitherapy
If you are into bees, propolis and BVT (Bee Venom Therapy), this is the place to go
Evidence on the Health Benefits of Supplemental Propolis
A nice article from the National Institute of Health
A thoroughly essay about Brazilian propolis benefits
Red propolis effects on cancer cells
Chemical composition of Brazilian propolis
Propolis Perfection - Bee and Propolis Products 