check out this link. Xerces Society put together an excellent Pollinator Resource Center specific to the area where you live. It's such a great feeling to get lost in a world of flowers and insects at this time of year! The website includes plans for homemade bee nests and more...really quite a gem for supporting and encouraging our native pollinators.
Bumblebee (Bombus sp.) on Bergamot (Monarda fistulosa):
Join the hunt for bees this summer! Check out the Great Sunflower Project to assess the health of your garden and contribute to scientific research.
Bees on sunflower (Helianthus sp.):
Live in the city? See Berkeley's Urban Bee Garden. In fact, even if you don't live in the city check this out. There's tons of good information!
P.S. The Fall 2009 Xerces Society magazine - Wings - is loaded with great information for folks managing natural lands. Invertebrates are often left out of considerations, often to the detriment of the whole ecosystem. Check this issue out if you deal with prescribed fire, mowing, herbicide applications, etc. or even if you don't. It's good to be in the know.