Do you have any modelling history? (design modelling)
If not its not going to be a pleasant time modelling and designing, I tried it once, nearly broke everything in the house out of rage.
But, if you really want to give it a crack you need to use Oxygen:
http://www.armaholic.com/page.php?id=1901 to make guns, cars, skins and the like.
Then, to make maps, you need Visitor 3:
http://www.armaholic.com/page.php?id=1907Finally, read these:
http://www.armaholic.com/plug.php?e=faq&cid=9 (Go to tutorials)
Then, if you havent punched your computer, and managed to produce something even half good I would love to see it.
But hey, you have my faith and my support (dont ask me how to use them, as I said, im not that good)
Thanks