I'm a first time MLB Fantasy player and our draft is today. I don't know if I should draft pitchers first or go for the other positions first.
Do I want a player with big home run numbers or a player that has better OBP, RBI, ect..
Basically how it goes is to not worry too much about positions at this point. What you really want to do is build on strengths and positional scarcity.
If you're playing in a head to head league, I downgrade stolen bases and saves a lot. These typically come in bunches so even if you have top tier talent in these areas, you aren't going to win them week in and week out. You want to get guys who are consistent. I go for guys with high OPS, and high power totals. In head to head, low batting averages don't kill you as much as in roto, so a guy like Adam Dunn goes MUCH higher in my book. He has an awesome OBP, hits 40 HR, gets 100 RBI, and scores 100 R per year.
Now, if you're in a roto league, you go for power/speed combos. You won't find a ton of guys who give you a good mix of power and speed. Guys like David Wright, Grady Sizemore, etc., are the types you want to try to get. I could go on and on and write a book.
I guess bottom line is with very short notice, you just draft the best players you can. You know the categories the league is using. Get guys who do well based on this. When in doubt use the default rankings. The best way to learn is just to play. You probably won't really get it for 2-3 years, and you may never get it (I have played for over 13 years and still play with tons of idiots).
One last piece of advice: fantasy is much much different than real life. There are no fantasy points for defense, "clutch", "gamer", or whatever irrelevant crap ESPN and other stations try to use. There are many guys who are better in real-life than fantasy. You have to seperate being a fan of the game and being a fantasy player. You can do both, but they both take on a different mindset.