How can you tell the number of vacant houses on a block? Easy. Just look for the houses with phone books piling up on the porch. The phone book spammers count those property-value killers into their circulation numbers, which is how they sucker businesses into buying listings in the yellow pages. Minnesota blogger Ed Kohler is even angrier about phone book spam than I am, and is on a bit of a mission to never have a phone book on his property again. So he got a little pissed when Verizon, a company he has no business relationship with, tossed one on his steps.