You might want to check out Power Leads Pro - it's a fantastic piece of software that grabs leads off the web from 20 different sources.
As for free alternatives, you can try using Manta. You can also use Linkedin and start friending the demographic you want to target. Then, once you connect, you'll be able to access their email address. You can put that into you email client and you're off to the races.
Another way is to email businesses that are posting in Craigslist. They're already expecting emails to come in from their ads, so might as well send them an email with your offer.