License Plate Collecting and how to find?

I know, I know, its always go to the junkyard and stuff, but I do get them there. I want to know an easier way to get them w/o having to go to eBay and pay like 10 bucks for a plate. I would just like to get them from anyplace and a price under $4. I, so far, have got about 30 from just collecting EG-- finding, getting em at junk yards and yard sales. Help me.