You also might want to pick up-

-a small pair of scissors and/or triangular shaped craft knife blades to trim the base

-some concealer to temporarily cover "oopsies"

-some butterfly clips to hold the hair back when you are doing attachments (especially until you develop your attachment method)

-Ultrahold and a white glue

-a few more types of tape to experiment with, especially blue liner

-plastic syringe(for dispensing alcohol) spray bottles (for alcohol/water,etc.), absorbent headband,

As Traco said, you will also need alcohol, a good shampoo and conditioner. The conditioner isn't as critical but be careful which sulfate free shampoo you buy. Most of them I have tried in the past were horrible for hairpieces. One thing to note though- don't worry about the alcohols in shampoo. I have yet to see any "bad" alcohol in one. They are mostly fatty alcohols which are actually good for the hair.

Also, I would have some leave-in conditioner laying around. I hardly ever use straight water to wet except to wash the hair. I always spray with leave in to re-style and right before removing to act as a buffer against the alcohol.