I Love 'Left 4 Dead'!

No really, I really love that game! I've barely played it myself acually, but I've been watching my two little brothers play it on the XBox, and it is so fun to watch! They've tried to teach me how to play it once, but I freaking sucked balls at it! Oh well, guss I just need more practice. I really think all the zombies on the game are so cool! The two kinds of zobies I love the most are the Witch and the Hunter! I also like the Molotov and the Boomer Bile! Totaly awsome game! And could anybody give me some beginner tips on how to play the game?
Thank you, Freddy1016. <3