You can probably look around on the reef Usenet group for people who are willing to give away their Mantis Shrimp (Its expected that you pay for the shipping of course).
http://groups.google.com/groups?hl=e...a.marine.reefs
Do a search like "free mantis shrimp" or something. Or post a message on Usenet and someone might respond.
My live rock took about 1 month to cure in a garbage bucket. I kept it in the dark and stuck a heater and powerhead in there. For the first 2 weeks, white fungus covered the rocks and the smell was horrible (Keep a lid on it). I did some partial water changes along the way. Through the end, many critters survived. I have tons of tube worms (small featherdusters) and copepods or amphipods that made it through. The bugs bred like crazy which was great for when I transferred them to the tank. My fish love to eat them.