Objective C plugin sample?

I know that this is the extensions list, but I don't see a general Add-
ons list or a Plugins list... If someone could point me in that
direction, that would be helpful as well...

I'm trying to re-write an old image-viewing plugin for the mac. The
old version uses QuickDraw (I said it was old) and resources (really
really old) and so it doesn't work in Firefox 3.6 (which is why I'm re-
writing it)

I know some Objective C, and so I figure I'm going co re-write this in
that using new-fangled Mac routines and nibs, etc. However, I don't
know how to start. I've got the BasicPlugin example that comes with
mozilla source, so I know how to create a plugin with entrypoints,
etc. However, I don't know how to create the nib, and how to interface
Obj-C with the entrypoints, etc.

Does anyone know of a more advanced sample for mac than
BasicPlugin.bundle? (Preferably simple enough that I can just look at
it and understand it...)

thanks.