This is a frequent problem. There are usually two situations:
1) you want to shoot the moon on its own (in the sky, no landscape)
2) you want to shoot a moon low over a landscape.
In both cases, the problem is that the moon is very bright relative to its "surroundings", so you want a fast exposure (1/80th-1/200th) and a narrow aperture (f/8 - f/16). Your light meter will tell you that's too dark, but try it. If you want a more accurate light reading, use spot metering or centre-weighted metering, as yellodog suggests, but don't trust your light meter too much and use the long end of your zoom with your tripod.
In the second case, the best solution (used by the pros) is to take two shots, the first exposed like above for the moon itself, the second exposed for the landscape, and then superimpose the two in post-processing.
I explain this in more detail in
this post. Sorry for the plug, it's one of mine.
Hope this helps.
Revenant