There aren't all that many green components, it's a fairly under-utilised colour.
That being said, you have the Gigabyte G1 Sniper boards which should fit the bill.
Memory comes in any colour you want, plus of all the things it's probably one of the easiest things to paint.
There are green cases, but they aren't terribly common. There were Nvidia themed Coolermaster 690 and HAF X models which I'd imagine aren't too easy to get hold of. There is the Bitfenix Prodigy's green variant, but as you didn't mention form factor I'd assume you are looking towards a more conventional shape.
NZXT have a black with green Phantom, and some cases like the Bitfenix Colossus have green lighting on a black case.
Ultimately, you can probably just use green LED fans on any old black case and you'll get a similar effect.