I noticed a lot of E-Commerce sites have so many products to sale, all of them are linked to other e-shops. I wonder how they get these products informations? now I know these called Data Feed, can someone tell me how to get Data Feed?
You can find datafeeds on most popular Ecommerce sites, news sites, etc. Creating your own isnt that difficult, but you'll need to decide how you want to parse it first.
rss2html.com will make a feed for you. You can use MSN or Y! to supply a feed and the script will put that feed on your site. It's free, easy to use and requires a little PHP knowledge (real basic - even I could do it).