Yeah, I found that Home Depot is about the most expensive place to buy granite. I remodeled a house that I sold last year and remodeled the house that I bought last year too. At my old house I got quotes from Keystone Granite and Granite Warehouse, both were competitive, I also got a quote from The Marble Center but they seemed a bit high priced. Granite Warehouse had a slightly lower price, but Keystone Granite matched Granite Warehouses' price. Both companies seemed reputable, but Keystone Granite had a better install time, and time to install was important so I could list the house for sale. Keystone Granite has a huge selection of granite on site and they did a really good job with the install.
On my new house I got quotes again and ended up buying the granite from K & L Building supply. They had the best prices on kitchen cabinets, although a limited selection, and the granite price was lower than Keystone Granite and Granite Warehouse. K & L Building Supply didn't have as good of a selection of the 3 cm granite, but we found one that both my wife and I liked. K & L Building Supply did not have much inventory of granite on-site, I think their main warehouse is in Portland. The install crew was Asian and didn't speak much English, however, I was able to communicate with them with a little effort and they did quality work. I bought the back splash tile from Keystone Granite just because they have the best selection and I performed the installation of the tile.