Here's a nice set of "globally useful" tips for folks starting out:
1. If you don't feel very confident in your own abilities to grade out players, then simply use the ESPN LiveDraft as your draft board. Here's the link:
http://games.espn.go.com/cgi/flb/livedraftresults
2. Go for balance. Balance as between hitter and pitchers, and balance among the various stat. categories. Don't completely ignore categories if you can possibly help it.
3. Unless you see a pitcher sliding, don't hesitate to spend your top 3-4 picks on hitters. Hitters tend to be somewhat more consistent, and less injury prone, than pitchers.
4. Conversely, don't let all the good pitchers go elsewhere. You want at least one top 12 pitcher, and a couple solid guys you feel good about behind them. You need a workable group of pitchers. If at least one of your pitchers isn't named Unit/Pedro/Schilling/Zito/
Prior/Maddux/Hudson/Mulder/Morris/Lowe/Mussina/Colon/Wood/
Oswalt or Halladay, then you are really, really going to be bumming. If you only get one of the above group, then be sure to spend at least two more picks on quality starting pitching as soon as possible.
5. Have fun. Relax. Mock other people's selections and don't take your own too seriously.
6. When the draft is over, assess how you did. Look at your team as a whole. Does it have enough backup depth at the various positions? Are you overstocked at one or two positions or stat categories, and need to think about trading to strengthen other positions that are weak?
7. Did anyone who went undrafted offer better chances of helping your team than any of the guys currently on your team? Alex Gonzalez as a backup SS might have seemed like a decent pick with your final pick in the final round cuz you needed the depth, but if Josh Beckett went undrafted... If you can pick up Hoffman and stash him on the DL as soon as the season starts...