British Mueseum pots
It’s stunning how many images of pots - historical and contemporary - are available online, particularly as museums work to get their collections represented digitally. Here are the search results (from Nasca stirrup jugs to a Bronze Age English beaker to the lovely Zen Tea Ceremony tea caddy pictured above) from searching for “pottery” on the British Museum’s collections...
best tutorial I've seen online
I just came across a great site for handbuilding ocarinas (traditional clay whistles). It walks you through the tools you’ll need, how to create a paper pattern for the body of the ocarina, beveling and sealing seams, creating the mouthpiece and soundhole, etc. Lots of support photos make every step clear. This would be as easy to do at your kitchen table as in the studio.