Welcome, Liz.
Sounds like you have some great plans.
You could try the plant database for bee-attracting plants. You can select for characteristics that include your zone, height of plant, flower season, size of flowers, color, leaf form, and--of course--bees.
I did a search for minimum Zone 4a and bees only, which generated 5,651 plants. Bet you can find some things you will like.
http://garden.org/plants/searc...