How can we find out which products in the market are using a particular patent?

I'm not exactly sure if you have a clear understanding of what patents protect - patents do not necessarily protect particular products per se, patents protect particular structures or methods. So, for example, if INTEL has a patent on a particular microchip, that microchip can be used in desktop computers, laptop computers, iPads, iPhones, whatever. The patent protects the chip per se, that is, its structure, not the product within which the chip is embedded. It would seem to me that you would be more concerned about whether or not a particular patent exists for your particular product/structure than what products are using a particularly patented device, product, or structure. In the same vein, you must become aware of any patent that you may infringe, meaning that your product or structure comprises the same product or structure covered/protected by that patent.