Also find a niche you know something about so you can write some unique articles and get better placement with the keywords in search results.. Target customers that want more information and most do before they buy. Many customers brows through several times before they buy something this give you a chance to provide more information so they might come back for more when they are thinking about other products in the future.
This is actually what I am doing but not sure if it will end up working. I find keywords that are somewhat popular ~200+ searches per month and check those keywords against how many results it brings up. If less than 30K results, then I go for it. It tells me the number of websites optimizing with that particular keyword / product. I'll keep you guys updated on how it goes for me.