I just posted a couple of pix in the Gallery and I'm hoping someone can ID the little guys for me.
Here is a link that might be useful: Bee Pix
Small Carpenter Bee (Ceratina Subgenus Zadontomerus)
The link below is very useful in identifying bees/wasps.
In any case, it's doing a wonderful job pollinating - just look at all the pollen stuck to the hairs on the underneath side of the thorax and back leg (in the photo of the single bee).
Here is a link that might be useful: Bee on Coltsfoot