The answer here ultimately depends on what the product is - whether its something you need to generate awareness of or is something you can capture existing demand for...capturing existing demand works if your product is the solution for a problem.

If you need to generate awareness....then FB ads and Google Display Network are the way to go, more on display network here: http://www.thesearchengineshop.com/how-to-promote-your-business-using-google-display-network

If there's already active demand or your product is a problem/solution type of product Adwords can work well