[Robomir]

I think it would be cool to have a different set for each important race. Men, Elves, and Evil in general.
Men:
K-Aragorn
Q-Arwen
B-Boromir and Faramir
N-Eomer and Eowyn
R-Helms Deep and Minas Tirith

Elves:
K-Elrond
Q-Galadriel
B-Legolas and Haldir
N-Glorfindel and Elrohir (I am runing out of Ideas.)
R-Rivendel and Lorien

Evil:
K-Sauron
Q-Saruman
B-Gothmog and Lurtz(the one Aragorn kills anyway).
N-The mouth and The witch King
R-Orthanc and Barad-dur

I have got a rather cheap plastic Lotr chess set which is not bad. It is only on the characters from the first two books however as it came out at the same time as the second film.