Ends up being USD $663.93, so $30 left over for a cheap mouse + keyboard or a heatsink if you plan on over clocking.
Keyboard + mouse is your choice really, they run anywhere from $10-20 to $100-200.
Overclocking, in simplest and slightly inaccurate terms, is putting more electricity through the processor to make it go faster.
Since you don't know anything about it I wouldn't suggest you do so; stick with stock cooling.