Congrats! My putter fitting yielded the best results/improvement over any other club fitting. Many time overlooked. I ended up sticking with my current putter as it fit me well...had to adjust length, lie and some weighting though.
Keep an open mind. Listen to your fitter and discuss your preferences with him (don't just go with whatever he says as gospel - you have to be confident when you look down)
Good luck

Go in with an open mind and trust what the fitter is telling you. Try to get a good warm-up in before!

Have fun! That is the most important part in my opinion...let the fitter do their job without your intervention and see where you end up!

Cheers, Chris

Jeff,
Go into the fitting with an open mind is probably the best advice you can have.
The process is super enjoyable. When I was fitted for a Scotty, it was (in my opinion) even better than being fitted for a driver.
JT