Now's a great time!

Here's a link to some information you might find helpful. One thing that's not covered in the link is that you need to plant so that the graft is above ground (including mulch, if used) level.

Here is a link that might be useful: Planting a Tree or Shrub

I planted dwarf apple trees (gala and other varieties) in my yard last year from Lowes. The deer trimmed the tree quite well :-)
This year all three are flowering this year. Once it stops to rain, I plan to go and put chicken fence around it so deer can't get to them and eat away the delicious leaves!