If you had $100 to spend on marketing for a week, what would you spend it on? Let's say it was an MLM opportunity. Adwords?
I would spend it on my product here: http://forums.digitalpoint.com/showthread.php?t=421257 Then I would spend some money on learning how to get small links for free. Best bet to do!
An MLM opp? I'd probably just pocket the $100 and walk away. But if I had to I'd give Adbrite a shot. Adwords is going to be way to competitive and is a losing proposition with only $100 a week.
I would get someone to do some social bookmarking then I would invest the rest in articles which would bring natural traffic over a long period of time.
I would run an ad in some MLM newsletter. I don't know where to find a popular one, but you are in the same business, so you'd probably know...