same thing as a wigger. a white guy who dresses like a black person/desperately wants to be a black person. has baggy shirts/jerseys/wife-beaters, chains, cell phone clips, backwards hat/visor, greasy bangs (aka Tobe-sicles), earrings, white tennis shoes, crappy low-riding trucks/cars, etc. they also try to imitate black dialect. you will notice a toby by how much he looks like a douchebag. rumored to have started in Lafayette, Louisiana. 2 high school baseball teams played each other, and one team had about 3 or 4 guys named Toby. They all matched the description above.
"a bunch of tobys were whistling at me today at the gas station"