Summer job help (first job)?

I'm 16 and I want to get a job but I have no idea where to start. I live in a pretty small town in california (tracy) and all the jobs seem to be taken. I want to get a job that pays all right and work maybe 5 hours a day. Something like holding up signs for newly built homes or something but I dont know who to talk to for somethign liek that What kind of work permit do I need and where do i get it and where do i search for these jobs. The online websites are only for adult jobs and i just want to make some extra money over teh summer. Thanks