I always wait to see how their personalities emerge and the name just kind of develops either by color or actions, however corny. Here are some of mine if it helps:
Speckled Sussex: Blossom, Durwin, Blythe (Looked up Anglo-Saxxon names)
Black Copper Marans: Fifi, Mimi, Tid Bit, Abe'lard (Since they are French)
Cukoo Marans - Gus (it just fits)
Americauna: Flapper, Choco, Jewel, Buttercup, Puffy (Cheeks), Speckalina
Cochin: Blackie/Downie
Naked Necks: Millie/Goldie
Jersey Giant: Big Bird
Creveceour: Frenchie
Polish: Oreo, Domino, Juliet, Buff Baby, Moppet, Little Bit, Crash (he is accident prone & clumsy), Wattles
Bantam: Napoleon/Gracie
Bramah: Harris
I tend to look up names from the original region of the breed and go from there if I can't come up with a name.