Most dragons leave their eggs unattended. Occasionally protected by loyal servants or something, but you don't have to kill the dragon for them or anything.
EDIT: @ SGI, that was another problem that I keep trying to warn him of. I mean I'm not just gonna out and give him an egg from the get-go. I'd make him raid a dragon's nest for it or whatever, and it'll be a while before they're even remotely strong enough to do something like that.
The conditions aren't that exacting. Red dragons need an open flame and/or an overall temperature greater then or equal to 140 F. Reds, Brasses, and Golds are the only real problem, for the rest it's pretty much keeping it in one location that somewhat resembles the dragon's native environment. Blue in extreme desert temperatures, Silver below freezing, etcetera.
Then you know, it'll take who knows how long to hatch it, then he has to be in the right place at the right time, from what I understand. Like don't you have to hatch a red dragon in a volcano, a silver in below freezing conditions, etc.?
(Using gold as an example) About 2 1/2 year to hatch, Six years to become Very Young and therefore large enough to serve as a mount. Look at about 17-18 years or more to become large enough to ride for the smaller dragons. 52 years for Whites, which is the extreme opposite example.
Then when it's hatched, what good will it be? His character'll be dead before the things old enough to be of any use in combat or as a mount. I said that and he said something about he's an elf and he'll live long enough. *slams head against wall* There's no getting through to him!