For cleaning it, two things i'd recommend:
1) milk. Milk will take the dirt off pretty easily. Just use toilet paper and milk. But give it a good clean afterwards with toilet paper and water (or saliva - see below), otherwise your fretboard will smell of cheese in a few weeks' time lol
2) saliva. Seriously - this is the best way I have found of cleaning the fingerboard. Same process as for milk - use toilet paper. Spit on the toilet paper, or directly on to the fingerboard.
I don't use specific cleaning products designed for the job as
a) they are expensive
b) they run out quickly if you have a lot of guitars (I have over 30, so would go through a lot of cleaning fluid in cleaning all my guitars),
and
c) to me personally, the fingerboards feel just, well, too 'slippy' when cleaning fluid is used on them.
Using cleaning products can get a bit crazy. I stick with the basic methods lol.
PS it was Bryan Adams' guitarist who told me about the milk trick. That's what he does when he sets up and cleans his own guitars (I was playing in a backing band one night Bryan Adams was playing, and was speaking to them after the gig about gear etc etc)