Originally Posted by
halfspeed
Floor pump. Flat kit. Decent bike shorts. That'll get you started.
Hard to disagree with this as your starter list. The floor pump is really important - you shouldn't use a frame pump (or smaller) to inflate your tires routinely as it's harder work, and most do not have a gauge. Topping your tires off to the correct pressure before every ride is probably the best thing you can do to avoid flats beyond not riding through broken glass etc.