The seeds are easy to start... just sow them into the soil, rake them in gently and watch for the heart-shaped leaves in the spring. The seeds not coming up in the spring may wait until next spring to put in their appearance, so be sure to transplant the seedlings out of the area into a permanent spot or pot them for later use. How many do you want?
Redbud Seeds require 115 days or so held in a moist medium at a constant temperature just above freezing. I use a vegatable crisper drawer. Another method would be to sow them in an unused corner of a flowerbed and simply wait for nature to run it's course. Sometimes seeds will not sprout until the second season.