Tournament Shark is great, and you may want to try out Hold'em Manager or PT3 and see if you like them better than PokerOffice. I know a lot of serious tournament players use one of the databases, either the Bluff PokerDB or Official Poker Rankings to get info on their opponents as well.
And don't forget my favorite tool, Google. I love to Google the screen names of my opponents and find hand histories that been posted involving them. Sometimes you can learn a lot about a player tat way, and most screen names are fairly uncommon strings so you'll relevant results on most of them right away.
Poker-edge can be great in tournaments, but be careful and only use it on sites where it's allowed.
The Sharkscope HUD can be very good too. If someone is a strong winning SNG player they are almost certainly a good MTT player too.
Get yourself some AHK scripts to make life easier for playing a bunch of tourneys at once too, they are really helpful.
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