The NaNoWriMo forums offer several resources for the care and handling of plot bunnies. Unwanted bunnies can be put up for adoption in the Adoption Society forum--prior to this forum's creation in 2010, they were offered in the Plot Doctoring forum. Plot bunnies that the writer wants to write later can be left in the Plot Bunny Day Care Center in the NaNoWriMo Ate My Soul forum, where they can breed with the plot bunnies of other Wrimos and be cared for in the finest fashion.
The care and history of plot bunnies is described in detail in Ilea For's "Plot Bunny Fields Forever: A Study in Plot Bunny Care and Husbandry", transcribed by Leo Fair.
Despite the similarity in name, the plot bunny is not synonymous with the plot ninja. There are various breeds, thousands of them, and many aren't even tied to writing. Inventors and scientists have their own breeds of plot bunnies that lead them to discoveries where A leads to B which jumps to G or even Z.