You are going to want and get some sort of stabilization (tripod or glidecam)
For editing you have final cut for mac, sony vegas for windows or adobe premier for both.
You are going to want and get an extra battery and some fast memory cards. Look at getting an ND filter and a external mic.
For lenses a lot of people will suggest a tokina 11-16 and a tamron 17-50 and depending what you are shooting a telephoto.
That's all video based stuff.