I usually buy prints online then find fabric to match at my LQS. The internet is also great to find "last years" fabrics or is your LQS doesn't have enough. You can do a search for the fabric you need. I use this place to search for fabrics.
http://quiltshops.com/
You can search 200 quilt shops all at once. Find the fabric you want then compare prices at all the different store.
For blenders I purchased a Moda Marbles card from Hancocks. This card has swatches of all the Moda marbles. You can match the color you want then find it online. It works great.