If you feel like trying your luck, here are the lines for UFC 87.
Here is a basic course for how to read these numbers, based on a $100 system:
(-) is for the favorite
This reads that if you bet the amount after the (-) you will win $100
ex) Brock Lesnar
BetUS: If you bet $260 for Brock and he wins, you will win $100
Bodog: If you bet $240 for Brock and he wins, you will win $100
(+) is for the underdog
This reads that if you bet $100, you will win the amount after the (+)
ex) Heath Herring
BetUS: If you bet $100 for Heath and he wins, you will win $200
Bodog: If you bet $100 for Heath and he wins, you will win $190
You can bet as much or as little as you want and these sites will calculate what you can win. Good luck everybody!

if brock was fighting coleman i would definitely bet on him. but i'm not sure about herring, he's a tough and seasoned fighter.
I dropped a little on McDonald because even though Maia is 7-0 and really good I think McDonald is more athletic and strong.
Betus sucks I've had nothing but problems trying to bet there. Bodog is way better and you get payouts twice as fast.