I have a pair of Eastern Redbud trees (3' tall) that I bought on eBay this
spring as bare-root plants. When I received them, I had neither time nor place
to plant a tree - so I stuck them into a pair of large plastic pots.
Can I get these trees into the ground this year, or should I try to
over-winter them in pots in the basement?

Redbud is a pretty sturdy species. Prepare the spot you want them very
carefully with lots of organic matter. Part shade is best. Dig good sized holes
& slip them out of the pots & into the ground without disturbing the roots.
Don't worry about fertilizer now, but water them every day it doesn't rain.
This will be better than trying to winter them over in pots, which would
probably be fatal.
Iris,
Central NY, Zone 5a, Sunset Zone 40
"If we see light at the end of the tunnel, It's the light of the oncoming
train."
Robert Lowell (1917-1977)