"Google for Gardeners" is a Google Custom Search Engine that I've been experimenting with. What I've been doing is hand selecting websites that have content that we as gardeners are looking for. When you search Google for something you always get the most popular results first but sometimes the most popular results are websites where you can buy plants or garden products.
This past fall I couldn't resist buying a couple of 1 gallon Sedums for the garden after they had been discounted. I planted the two Sedum 'Autumn Joy' plants in the garden hoping they would still have enough time to establish themselves before winter hit.