check out www.servicemagic.com
www.landscapeleads.com

They will advertise for you on leads. I found servicemagic.com is helpful alot. You have to pay for leads but least you dont have to do alot of work to market and pay a high price to advertise in phone books.

I dont do that much of residential due to fact they will drop you in a hurry no matter what, also more picky, and alot of other factors.