Hi Richard,
In the early spring we will distribute flyers to certain neighborhoods we feel we have penetrated well or wish to penetrate. When any crew goes out to do work, we ask they walk flyers to about a dozen houses surrounding the job site. We feel the neighbors closer in are the most likely candidates. Also, hitting just those few houses takes less time. You're aiming for the domino effect here.
For mass distribution, try postcards, val-pak, or another print ad of some sort.
Just remember that everythng has a target, and it doesn't make sense to walk 500 flyers a day or a week if people don't have a frame of reference. But, if they have a reference 3 doors down, well, they might just call you.
Beth