A while ago I took glassblowing course at Jim McKelvey's glass studio in St. Louis. McKelvey co-founded Square -- he was selling these amazing glass faucet spouts[1], and he lost a $2500 sale one day because a lady wanted to pay with her Amex.

He wrote an instructional book[2] on glassblowing that's pretty good.

[1]http://www.glassfaucet.com/

[2]https://www.amazon.com/ART-FIRE-James-McKelvey/dp/0978683110