Halo CE - Purchase and Download online?

Can I do this? I recently have gotten the urge to play this game again and I visited my local shops but none of them sell this game, I don’t really trust websites like Amazon or Ebay, so if you could give me a website that sells Halo CE and allows me to download it when I have purchased, that would be awesome.

You can purchase and download Halo: CE from Xbox LIVE for 1200 MSP ($15).

For PC?

Nope, that’s just for the Xbox. I’m personally not aware of a PC download, but perhaps someone else can help.