For 30 years Daniel Smithhttp://www.danielsmith.com/ has catered to artists. They have materials that mere hobbyists don't need, like 23 carat gold leaf, dry pigments, encaustic waxes, studio furniture, framing supplies and materials for many other types of projects. They make their own oil paints, printmaking inks, dry pigments, gessos, et cetera. There are many classes taught there, and usually someone on staff with experience using whatever tool or material you might wish to purchase, or at least they know someone who does. They don't have everything, but are one of the best places to start your search.