This is the wrong section (I would have put it in off-topic), but who cares. Anyways, as for the "Owners" of Bukkit, there really aren't any. Though, the founders are are the CraftBukkit Team. Which, from what I know, consists of EvilSeph, Dinnerbone, lukegb, TnT, and NuclearW as Administrators. More information on staff members can be found here.
Bukkit is open source software so anybody who has ever contributed code to it "owns" it. Ownership of open source software is pretty meaningless anyway as anybody can take the code and do whatever they want with it as long as the derivative is also open source (for example Tekkit).
As pretty much everyone has said, although it was founded by EvilSeph, Dinnerbone, Tahg and Grum, there have been a large number of different contributors since the project began, from the developers who have submitted code for the project to the staff who have contributed time moderating the forums, approving stuff and working on the site. It's very much a community project and community effort.