I have an Eee 1000h and it only has 2.0.
Don't worry, as the others have said, 3.0 hardware is backwards compatible to 2.0 so you're golden.
If however you want to install 3.0 support with the precious speed advantages, then I don't think there's much you can do, as the motherboard doesn't allow it and it doesn't have a sufficiently fast enough bus for any additional card-based solutions if you are into hardware hacking.
So: Don't bother, take 2.0 speeds with the 3.0 hardware or pick another computer. Glassed Silver:mac