I hand quilted mine, and by the time I finished making the blocks, I had all but the last one quilted too. I only quilted through the block itself and the batting (no backing). Then I assembled the top with its narrow sashing, and finally backed it with a wide backing. In order to attach the backing to the top/batting sandwich, I quilted in the ditch round every block through all three layers.
You can see a bit of how I put the blocks together on the Thread we had/have on the board.
http://www.quiltingboard.com/t-28063-214.htm