You might also look for recordings of Suite Bergamasque, of which Clair de Lune is the 3rd movement.
Folks have already pointed out Gieseking and Richter, but Thibaudet has also recorded all of Debussy, including this work. A quick check of ArkivMusic shows a number of other recordings: Ciccolini, Pascal Roge, Klára Körmendi, François-Joël Thiollier and quite a few others.
Incidentally, if you have never looked at the web site for ArkivMusic ( www.arkivmusic.com
) , they have an excellent browsing tool for tracking down all the different performances of a particular work (as well as a lot of other nifty search features).