Do you have a specific reason for going to Geneva? I haven't been, but that's because it's always cited as a non-highlight of Switzerland. Not an awful place, but an expensive one lacking in appeal compared with the rest of the country. Again, I don't have personal experience.
From Paris to Geneva you will take the direct TGV, booked on French Rail http://en.voyages-sncf.com/en/
or Capitaine Train https://www.capitainetrain.com/# (the latter is often easier for US residents to use). Tickets are much cheaper if you book early and can accept non-refundable and non-exchangeable fares, and prices go WAY up closer to travel or if you need flexibility. If you book early enough, you can get first class for only a few euros more than second class - a win-win.
For more on this train, see The Man In Seat 61: http://seat61.com/international-trains/trains-from-Paris.htm#Paris-Switzerland
I'll let others who know more answer the second set of questions, except to say that you can find schedules on Swiss Rail: http://www.sbb.ch/en/home.html.
To find train schedules easily for most of Europe, you can use the Bahn (German Rail) website http://reiseauskunft.bahn.de/bin/query.exe/en, following Rick's tutorial: http://www.ricksteves.com/travel-tips/transportation/trains/online-schedules. However, this will only have prices for trains that start or end in Germany (so, not for your routes).
