How are we to cope with information overload and decide what to purchase?

Never before have we been bombarded by so many products. The internet seems to be a collection of shopping malls where one can find anything from the best toothpaste to the latest cure (to just about anything). Human beings are a curious lot; we are intrigued by products, no matter how implausible, silly or exaggerated their claims are. How do we cope with all this information and decide what to purchase?