WayneLigon
Adventurer
It depends on the campaign 
1. Ashara: All the elves are dead, so it's a moot point
They are the 'forerunners' of the campaign. People know they existed long, long ago. They all died somehow. The half-elves are still around, since elven 'blood' does not thin very much over the ages. Even though people have no idea what elves even looked like (most extropolate from half-elven features, which is kinda sorta close), they blame/attribute to them most of the wonders of the ancient world.
2. The Fallen: Elves here are a fallen people, and are pretty Tolkien-like in that they once had a proud history now come to ruin and they are slowly dying. Their huge city is now the home to a Great Wyrm Green Dragon, with his legions of lizardman and troglodyte followers. Where once elves were immortal, now they die, and they seem to die sooner every generation. All elves are very very close in physical appearance, like brothers and sisters all sharing the same parents. Which they do, kinda.
3. Dragonsong: All elves here are descedents from dragons, and are mostly Lawful in outlook. They are more fully described in a
d20 Weekly article I helped write a few weeks ago.

1. Ashara: All the elves are dead, so it's a moot point

2. The Fallen: Elves here are a fallen people, and are pretty Tolkien-like in that they once had a proud history now come to ruin and they are slowly dying. Their huge city is now the home to a Great Wyrm Green Dragon, with his legions of lizardman and troglodyte followers. Where once elves were immortal, now they die, and they seem to die sooner every generation. All elves are very very close in physical appearance, like brothers and sisters all sharing the same parents. Which they do, kinda.
3. Dragonsong: All elves here are descedents from dragons, and are mostly Lawful in outlook. They are more fully described in a
d20 Weekly article I helped write a few weeks ago.