Just read some game reports.. a lot of them are helpful, if you can find the more verbose players around here. Sulla in particular has very good stuff.
If you just want to win Noble, arrange the situation to your benefit.
I lost my first noble game, but on my second, I set it to "inland Sea, no wrap, small, Ghandi" and won easily. Ridiculously so, in fact. Thanks to good diplomacy (yay missionaries) and easily defended boarders, I could ignore military and run near 100% science for most of the game. Had tanks, infantry, and Aircraft carriers (Though admittedly not a lot of them) while the second place civ was running around with cavalry, rifles, and galleons.
Or find a good friend and play a hot-seat allied game to learn the ropes.