It depends on what do you plain to do
If you need it for web design graphics Photoshop is the most powerful choice, if you need it to print at small size Photoshop keep being the best choice, but if you need to print reasonably big then you should use vectors.
For traditional graphic design I preffer Freehand (from the old Macromedia), its much more stable and run faster. For illustration then I would choice Illustrator.
Accesories?
A pantone if you want to print accurate colors.
A wacom tablet if you plain to paint or draw though it works much better with Photoshop.
Lot of patience