Ladies and gentleman of the D.Gray-Man Wikia community, I have wonderful news~!
mangafox is one again hosting the D.Gray-Man manga chapters, and they have the Pilot Chapter, Zone available for reading! In English!
You can find the one-shot here, and I would suggest that if you want to enjoy it that you do so now, because mangafox had previously had to remove D.Gray-Man due to licensing issues. I don't know why they've reposted the chapters, but they may well have to take it down again, so read, read, read!
^.^ Enjoy, all~!