So basically I should teach you how to shoot skiing in 30sec 
I'm pretty sure it won't work, but why not to try
As far as equipment goes, you are fine. I normally use 1d (now 1 mk4 and 1 mk2 body) and 17-40/4 (for some features) 70-200/2.8 (mostly for finish area), 300/2.8 and 500/4 and 1.4x converter going to each of these lenses if needed. But thing is, I'm shooting alpine and cross country skiing World cup races, where positions are limited, and at least on alpine skiing races also quite far from skiers (especially on DH and SG). Freeskiing is completely different thing. You are not so limited, you can move around, and what is nicest of all, you tell guys where you want them to be, not that gates dictate where they will ride, and race director dictates where we can stand (no I don't have anything bad to say about race directors on WC, since they are really great guys).
Shutter speed... anything from 1/60sec to 1/4000 or even 1/8000sec, depending what you are after. For crisp sharp photos, where you want to eliminate any chance for motion blur, go with times faster then 1/1000. Outside, and especially with today's camera, this can be done easily. If it doesn't go other way, put is to 1000 and you are good, since even so cloudy day, will be bright enough to do this.
Aperture... Normally I don't want my background to be "visible" so I normally shoot at f3.2 or f3.5, but there are photos like this
, where I actually want background, so I change aperture appropriately.
Angles... depending what you are after, and depending with what kinda riders you will be shooting. I have no problems shooting (out of races of course) with any of WC guys. I tell them where I want them to be, and they ski on 1cm accurately exactly where I want them. I can do this also with my brother, but we both were racing for almost 20 years, so we have "a bit" of experience on skis. This way, I can really lay on snow, put wide angle on and shoot them when going 30cm away from me, without being worried anyone of us will get hurt. On the other side, I have really bad feeling doing something like this with riders, who can't control their skiing (at least so accurately). When skiing by at 80+km/h, hitting you is last thing anyone would want. So with people who don't ski that great, I rather go for a bit safer way. Sure photos don't look all that great, but I rather stay alive 
So if I could choose, 90% of my work would be done with wide lenses, but since I can't 99% of my work is done with 300 or 500mm lenses.
Anything else? Sure... go manual. Don't rely on your camera's "brains". They are just too small to handle such things. You will never get properly exposed photo this way, so go manual. Go for skiers face, and screw snow. It will be overexposed, but who cares about this. It's still better to have a bit overexposed snow, then underexposed skier. Afterall it's about skier, not about snow crystals 
So, will this do?
