Firefox extentation - needed

Hi, I'm looking for a firefox extentation expert, previus expirience is a MUST. The extention will work with our BACKEND SERVER. Need to know how to save an ID on the extantion and send it to the server on every request The extantion first screen presents a list of Services when user hit a service he get a list of directories when pressing a directory user get a photos gallery (very simple just show the photos). that's the basic, please send your hour rate, this is a long run project (devided by steps) we'r looking 4 a long term work.