I know craigslist has been mentioned but do not forget backpage. I prefer backpage over craigslist because I can post the same ad to multiple cities while adding an image quickly.
We need to approach advertizing in a way that someone seeking an opportunity would approach it. For example, if you're searching Google for a business/work-at-home opportunity, you're not likely to type the words "classified ads," are you? You would most likely search the words 'work at home opportunity' or 'business opportunity." This is where you want to put your ads.
Your local newspaper online might have free ad posting. Craigslist is good, Ebay has free classified, and I was just introduced to usfreads.com, which looks promising.
I am always searching for new ways to advertise for free. I am not sure of we can share links here or not but I am willing to try. I found a ton of free advertising here: http://www.squidoo.com/promoting-your-website-to-millions-of-people-for-free and I also like to use Twitter. Contact me if you need more help.
Don't believe everything you hear about free advertising. Do your research to make sure you are getting a good referral. If it is supported by SFI, then you can be assured it has been tested. Just be ware of free advertising suggested by any and everyone on SFI as I've found some of them to be somewhat sketchy. Again, be a smart business manager and spend your marketing dollars wisely.
