I've got a good bit of experience with this, and I'm Danish, so I know a bit about how it works from that point of view. I'll reply in English in case someone else might want some advice.
First of all, from my own experience, there are some places and countries to avoid, and some jobs as well. However it depends what you want to get out of your ski season, my goal was always to ski as much as possible.
With that in mind do not become a ski instructor or rep (we call it guide in Danish). Those jobs leave little to no time for skiing on your own. In general I would also stay away from France, it's crappy pay and crappy living conditions. A general list of jobs to go for could be:
Bartender
Waiter
Dishwasher
cleaning jobs
Nightwatch at hotels
Shaper in a snowpark
Especially the last job is pretty cool, it's how I got started in the snowbusiness. If you want to work in Austria, Italy or Switzerland as a shaper, some good companies to apply with are either Qparks or Schneestern.
In norway the resorts tend to take care of their own parks, some good places to look at would be Hemsedal, Trysil, Geilo, Hafjell and Kvitfjell. All of those Places also hire people for a number of other things, like cleaning, waiting tables, working in a kitchen etc.
I think the best way to do it is make a shortlist of places you'd like to go, and then narrow the search down to those places. Questions to ask yourself when it comes to finding good places are:
What kind of skiing do you like, is it mostly park, mostly off piste or maybe a mix?
How important are things like night life, accomodation, other things to do besides skiing?
Are you on a budget, or is money not a problem?
This is just off the top of my head, feel free to PM me with any questions. My areas of expertise are mostly Austria and Norway, so if you wanna go somewhere in one of those places, I can definitely help you out.
Cheers.