DirectX 10 cards

I need a list of existing Graphics cards with Direct X, please, so I can go and research then on the net (prices and specs).

Also, until mid-range Direct X10 cards are available (When can we expect them?) what are the three next best PCI E cards around? The motherboard supports ATI Crossfire dual card set-up.

Also, I am thinking of apgrading my own pc: should I get more memory or a dedicated graphics card? At the moment I have ATI Radeon 200 Express onboard chip and 768MB of DDR RAM. CPU is AMD Athlon 64 3200+ and OS is XP home.