tubafeak
Weight is the enemy.
You could go to a local speed shop and, in exchange for a periodic detail of the head manager's (or someone of similar decision-making power's) personal car (probably rather nice looking if they manage a speed shop), you would ask them to hand out your brochures/cards and verbally reccomend them. Thsi way you would get a better return on your investment, you'd establish a more dedicated client base (who were probably already doing hand washes with actual car wash soaps) who would genuinely appreciate the work you were doing. Local paint shops would be good too, provided of course that they didn't have their own "detailing operation" in house.