Sorry you didn't get an answer the first time around. Let me try again.
As for where to advertise the flyer job...The only thing I can think of right now is Craigslist. But I'm not sure I would trust someone I find on Craigslist. Hopefully others here can help. I'll keep thinking about it, and if I think of something else, I'll update my answer.
Other Considerations: Do you have a Twitter account and/or Facebook Fan Page? If so, you can advertise the job that way. If you don't, you should seriously consider it. That's a good way to not only advertise these jobs, but also advertise your product. I looked at your web site (got the link from your other post) and didn't see a Twitter or Facebook badge on your site.
Another option is to involve your current customers. It sounds like you have some happy customers. Consider asking them to spread the word. Maybe instead of getting people to hand out flyers, you can give your current customers the commission for referrals that end up purchasing your product. You can even do a combination of both people handing out flyers and customer referrels. If using your current customers, you may also be able to offer a discount on their next purchase.