as far as current customers go start a referral program and then send them postcards or meet with them one on one to launch it.

for new customers: how about going to some chamber or business networking meetings? you can find many people there who will be looking for or need what you have to offer.

Also what about some marketing of your website.

I have free lessons and all kinds of ideas on my blog at http://www.onlinemarketinglessons.com