The easiest way to get specific product feeds from multiple suppliers is through an affiliate ad networks such as Webgains or CJ . The Networks significantly reduce the amount of labour needed to get product feeds from various merchants. These ad networks allow you to select the data feed with a choice of parameters to include in the download such a program, category, product, description etc) and file extension types (xml/csv). You will need to be technically gifted enough to import this data feed into your database, after you have set it up, and then display the merchants products on your site, this will be discussed in another post. You must be a member of the ad network and be an affiliate of the merchant to use the service. There are modules and plugins starting to appear for popular publishing platforms such as wordpress amd joomla which will allow the non technical to display the feeds on your site. There are other 3rd party’s which will setup the who thing and display the products you select on your site for a fee, so there are many options as to how you acheive this without being a gifted developer.