I usually take a long term approach that provides great natural search results ( i.e. having a page appear prominently in page rankings on search engines for keywords specific to the company I am promoting ).
I build a small landing site, usually about five pages, that provide great info on the products or company without being 'spammy'. Then I take out ads on various sites that have high
PR ( page rank ) for content related to my site. I used to use Overtures keyword tool to find the top search phrases that are searched related to my business, but that isnt really active anymore, so I use the free tool at
http://www.keyworddiscovery.com/keywords.htmlfor the same thing. For example, if I was promoting Xango I'd put in Xango and see how many searches come up for related phrases like "xango mangosteen", etc, and build some of my content around those words.
Then Isually I do free trial adson sites like
www.wampros.com under the company I am promoting so I can get my site spidered by the search engines.That gets my page into the search engine, pluspasses my site "link juice" to help it rank better,but I set a reminder in outlook to tell me to cancel the free trial before it expires. IfI want to take it further, I take out paid ads on other work from home sites to increase my incoming links. the benefit is that over time, my page will build up page rank and hopefully I will get direct search engine traffic for people searching for info on my opportunity, rather than blind ads on craigs list where I'm hoping soeone interested sees it -
I've also used safeleads.com with some success for direct marketing, but I really had to tweak my ads until they were not spammy so that I would get consistent responses.