I had Fallout (Non GOTY) but now i don't, is the GOTY modable and is it as easy as Non GOTY?

The only difference is that the GOTY has an extra disc in the case with the DLC on it. That's all. It's still the same game.

If anything it's easier.

I think I'm right in saying that downloaded DLC was placed in some obscure folders that had to be moved before you could play a modded/dlc game. With the GOTY all the "DLC" is placed right in your Data folder ready to go.

Just remember to install it somewhere other than Program Files if you're running Vista/Win 7 to avoid UAC issues - C:\Games\Fallout 3, or the like.

~Xeph'