I started on foot and did exactly what you described, making my way over to neighboring companies and peeking in their dumpsters. If I noticed goodies, I just asked someone around if I could take this or that. Eventually one place started laying stuff outside for me (until someone else noticed and started picking it up before me). Walking is also a great way to meet people and notice things you don't when you're driving.



Good luck to you and may you find a cash register full of cash! (My first wahoo! moment scrapping, it wasn't full but I didn't complain about the $95!)