I was looking for some good reading material and came across this...
http://www.scribd.com/doc/18406/193-...arketing-Ideas
A lot of it may be more geared towards brick-and-mortar type businesses and some do require a bit of an investment, but there were some pretty good ideas in there.
For instance, #51 says to provide your friends, family and best customers with a couple of postage paid envelopes and copies of your sales material (brochures or what have you) and ask
them to address them to their friends and have them include a "personal recommendation" on your brochure.
It would take them just a few minutes to do this for you and they would probably tend to send them to people who they think could really use your services (more targeted than just sending them to local businesses). If you gave 10 friends 2 mailers each, you've just reached 20 people who may have a real need for your services that you wouldn't have been in contact with otherwise AND you didn't have to do a thing except provide the materials.