I have had this handy Bee Basics: An Introduction to our Native Bees booklet available on my Biodiversity page, and I thought I would highlight it here as a free download (or, you can take yourself over to Amazon and pay $27 for it. Seriously!)
This 48-page gem is full of lovely drawings and jam-packed with interesting tidbits. A gift to you from Pollinator Partnership, the USDA, and the US Forest Service. Make friends with your backyard bees.