the Draconomicon goes through almost all of the other dragons. The OA (Lung) dragons are different though, since the don't have standard breath weapons or elemental immunities (usually) ...
if you follow domino's suggestion you'll get just about every other dragon type out there. If a dragon has more than one resistance only pick one (same for breath weapons).
if a dragon doesn't have those you might want to give them some other ability ... swim speed, waterbreathing or ability hold breath underwater for hours instead of minutes ...
if it doesn't have any of those, then just don't give it (the Half-Yu Lung/carp dragon's only special ability is waterbreathing ... no immunity, no breath weapon)