I recently took a series of three intro to glassblowing courses at Revere Glass in Berkeley, California. Our teachers were very helpful, the workshop itself well stocked with tools, and the glass was plentiful. The fish sculpture below is the output of my third course.Glassblowing has proved to be an interesting combination of art and science. We'd seen its master craftsmen at work in Venice and shaping glowing, flowing, 1000C hot glass proved as challenging and fun as I'd imagined. You can let your creativity loose yet still have to respect and be conscious of the physical properties of glass. The difference between cold and hot seals, flashing your piece to prevent cracking, constantly rotating the glass to maintain control over it, how to work "frit" or colors into your piece, and much more.
All in all it was a great experience and, if you're in the Bay Area, I highly recommend Revere Glass (watch out for their Groupon offers).