Bees on the Catnip

When we moved into our current house it helped that there were already many perennial plants in, including catnip and hollyhock all along the front yard. The bees and other pollinators have enjoyed these all summer.

I have noticed so many different pollinators, in fact, that I interlibrary loaned The Bees of the World by Charles D. Michener to try and identify the many different bees. The book, however, is 600+ pages and covers a lot of the technical aspects without necessarily helping with identification. A good book in its own right, but not what I needed for identification (however, if you are interested in classification aspects and historical development of bees I would recommend it).

Does anyone know of a good bee identification website? Here are a few of my bees on the white-flowered catnip. Click on the image for greater detail.