I would like to know what are the best 3 even 5 places to promote a product , places that most of the people will go to get something they need Thank you
Where do you go when you're looking for something you need? When most people want something, they'll turn to a search engine. In my opinion the best place to show off your site is there - either in the search results or PPC advertising on a search engine. Of course there are plenty of other places, like craigslist and forums - and most of them get indexed by search engines. Squidoo is pretty popular for articles too. But there's really no list of top places.
PPC is the most targeted.. but comes at a cost articles are also fairly targeted... free forum posting.. not too targeted.. free I think articles is a great way to go.. but do not send directly to the vendors page.. make a site about the product.. and collect emails!
Research your product, research your market, research where and how similar products sell best. I find this question very general, put your marketing cap on and think about yourself being the customer, where and how would you go about getting that product? In general yes search engines (ppc or organic), manual labor (get in the trenches, write some articles, give the product some publicity, get some backlinks from relevant products/buyer bases), forums/social sites/and probably most important of all, getting others to help you sell it if it is your own product. If it is not, the perfected formula that sells best for each product varies, the only real way is trial/error error error until you find conversions/money and repeat.