Guys, I have every single game of the first decade except the original C&C. How can I get my hands on this without going and buying every single game?

the best places are ebay and amazon and just keep looking because one will come up for sale sometime. Or you could even try at games shop that sells loads of 2nd games or ask in a shop to see if they could get hold of it for you

First I think you should stop looking for "Tiberium Dawn" and consentrate on the name of the actual game its Command & Conquer, not Tiberium Dawn.

This was supposed to be the name of the game, but as you can see trhere is no such game. Even in Europe ppeople ask what yyou guys keep calling Tiberium Dawn, and i only recently found out, after thinking i was missing a game in the series, that Tiberium dawn is the original c&c game, and in my opinion the best
They have multiple copies of this here in Ireland. I myself have 5 copies of the game in different offers at the time.

If you wnat one that bad i mite be persauded to sell one to you..................

You can download the original Command & Conquer for free from EA right here. And IrishStar is correct, "Tiberium Dawn" is just a nickname given to the game by fans in order to distinguish it from the rest of the series.