Watch people play for a while, and (outside the game) ask questions...but don't make a pest of yourself.
Buy some pre-made decks and sit down with another newbie and go at it, then swap decks and do it again.
Buy some booster packs, then tweak the decks and repeat.
I've met people that play Vampire decks, Zombie decks, Angel decks, Weenie decks of any/all colours (weenie means essentially 1/1 creatures), denial decks (deny the opponent any cards), blast decks (no creatures, pure damage spells), and almost any other type of deck. Some swear that their deck is the only one worth playing, others will swear that that type of deck is not worth playing. I've seen decks that are pure cheese, and decks that are pure "OMFG!"... I've seen 60 card decks worth less than $3.00 beat decks worth over $100.
Magic is pure luck mixed with strategy...the strategy is combined in the building of the decks and the planning of possible combinations ahead of time, and on the spot based on what is in your hand. The luck lies purely in the draw...you have to shuffle (i.e.: randomize) your deck, so that you will not know what is coming.
I've seen players concede with winning combinations in their hands...but with no mana to put them out. I've seen players unintentionally elongate a game simply be not paying attention to the cards in play (Icy Manipulator on his side, City of Brass on the opponent's). I've seen/heard of players loosing because they failed to consider what a card they played would do (in one case, the card gave all creatures +1/+1 for each other creature of the same type in play...the caster failed to account for the effects of a global enchantment on his opponent...whom had about 10 0/1 tokens in play...). I've heard of one game where a person used a card which allowed him to switch two permanents (one from his side for one from his opponent's side), and he "gave" his opponent a high-powered card that said "As long as <this card> remains in play, you can not win the game, nor can your opponent loose the game." He then proceeded to beat the snot out of his opponent, because he had nothing to get rid of the enchantment, not the creature itself...
Outside that ... go to the MtG forums on the WotC website and join it. Try not to deluge the boards too-much at once with questions, and read and *pay attention* to what is on the forums. These are (generally) players that have some experience with the game.
Good Luck!