First i5 build what next? (few Questions)

[Hitlist]

Hey iv been looking at parts for a bitnow and iv finaly got;

asus p8z68-vpro
i5 2500k
8GB vebgeance
antec h20 620 cooler
and a corsair ax850

My question is what do i buy next, i already have a monitor and OS.
I am not clued up on SSD's, keyboards, mouse or anything else, i am also looking at going SLI maby two 570's is it worth getting the evga classifieds?

Thanks
Aaron

 

[stulid]

Spoiler

Surprised no one has responded yet.