I'll mention a few lenses.
First is the Canon EF 70-200mm f/2.8L IS II. This is sort of the "gold standard" for the 70-200 lens. It's considered a "bread n butter" lens by many pro shooters. I own the original version of this lens (no the "II" edition) and love the lens. The only downside to this lens is the price tag. If money were not a consideration (sadly... it always is) then this would be THE lens to own.
Canon
EF 70-200mm f/2.8L IS II USM Telephoto Zoom Lens
Retail price on this lens is $2500. There's a $200 instant rebate bringing it down to $2300. This is probably more than you were hoping to spend.
Next is the Canon EF 70-200mm f/2.8L. Note the "IS" tag is missing from the name. That's because this lens does not have image stabilization. Image stabilization is helps reduce motion blur caused by camera movement (and ONLY camera movement). Minimum shutter speed to prevent motion blur is a guideline that says the minimum shutter speed should be 1 / (focal length) X (crop factor). Your crop factor is 1.6. So on this lens with a max of 200mm focal length, the minimum shutter speed to prevent motion blur is about 1/320th. As you'll be shooting 1/500th, motion blur should not be a problem and therefore IS shouldn't be necessary. This is a very popular lens specifically for sports photography because the shutter speeds required to freeze action are high enough that having IS is no longer a factor.
Canon
EF 70-200mm f/2.8L USM Telephoto Zoom Lens
Note the price tag is considerably less... it retails for $1450 but has a $100 instant rebate bringing it down to $1350. Zoom lenses with a constant f/2.8 focal ratio aren't cheap.
There are two other lenses you can consider... but tread carefully here. Sigma makes a 70-200mm f/2.8 which does have image stabilization (Sigma uses the letters "OS" for "optical stabilization"). At about $1300, it costs about $50 less than the non-IS version of the Canon lens. Tamron makes a 70-200mm f/2.8 which does not have any form of image stabilization. It's the least expensive 70-200mm that I know of ... at about $770.
The reason I mention that you should tread carefully is that Canon (and the same is true of Nikon) do not cooperate with 3rd party lens makers. They have to reverse engineer how the camera communicates. It's not unusual to read reports of people who claim they get strange error messages from the camera when using these lenses... or that it worked fine with the camera body they originally owned, but started getting error messages when they upgraded to a newer camera body. Optically, both Canon lenses (with and without IS) are better than the Sigma. Optically, the less-expensive Tamron outperforms the Sigma. The downside of the Tamron is it's focus motor -- it uses a more basic micro-motor which is slower to focus than any of the other lenses.