A few friends, (6 of us), used to play this every New Year's Day. It is a long game and we rarely finished. Our friends owned the game and explained the rules. It is involved enough that you want to read through the rules a few times.
There are some game aids and summaries on BGG:
http://www.boardgamegeek.com/boardgame/71I notice there are lots of links at the bottom of the game page to Civilisation sites. They may have tutorials or resources, be sure to check them out.
There is even a Wiki for the game:
http://en.wikipedia.org/wiki/Civilization_(board_game)