I have a weird relationship with spinning. I'll go a bunch of times, think that I am all into it, and then I don't go for 6 months or more. I went to two spin classes last week. On Friday I went to Cycle Tech with Melissa Soss and on Saturday I went to Studio Cycling with Damian Vella. I wish I could explain to you the difference between Studio Cycling and classes with fancier names, but honestly, it's all the same to me. My favorite spin instructor is Craig Eisenberg. His enthusiasm is contagious, which is really helpful when you are huffing and puffing up an imaginary hill and praying to the fitness gods that the class will end.
I never invested in a pair of cycling shoes. I hear that they make all the difference and I would probably have more efficient peddling strokes. Tim McNamara, also an Equinox cycling instructor, recommends Pearl Izumi shoes. He also says that Zappos.com is a good place to order cycling shoes from because you can order a pair in multiple sizes and return the ones that don't fit free of charge.