TheRealSaxman - 10:13 pm on Mar 4, 2013 (gmt 0)
Generally eCommerce websites have a product feed that they allow you to download. Many eCommerce Shopping Carts also have a specific "compatible" feed they have set up just for Google Merchant Center... although many that I have used are outdated and always seem to have the need for manual updates. When I find that a client doesn't have the resources to pay me to build them a feed from the ground up (for all of their products) I will generally let them know that I can build a test feed that will target only a few of their most popular products. After letting the test feed run for a few weeks they start to see the value and can then justify spending the money to build a complete feed. When I build the feed myself I always like to utilize Google docs as they have all the attributes setup already, and the upload is much easier.