Hello,
I'm not aware of any specific courses for transatlantic & US flight planning, however a good start would be to download and read the MNPSA Operations Manual. A large proportion of it is flight crew specific, however there is a chapter for guidance to flight dispatchers (Ch.15).
http://www.nat-pco.org/mnpsa.htm
In terms of flight planning systems they should all take into consideration of the current tracks (I know Jetplan certainly does). Suitable alternates will have to be chosen by yourselves based on your company SOP's. It's a good idea to read the MNPS guide to make yourself aware of what you can and cannot do, e.g. climbing/descending on tracks, when you can join and leave tracks etc etc... There are many Jetplan route inputs for track flying, they are all listed in the user manual (accessible on Jetplan.com).
Flying in the US is pretty straight forward (just make sure Customs & Immigration know you are coming in the first place with the correct paperwork). This thread has some more information on US ATC procedures:
http://www.pprune.org/forums/showthread.php?t=308870
Oh and don't forget to arrange your TSA Waiver in good time should your operation require one. NOTAM FDC 6/7435 contains the latest version of the requirements I beleive.
Hope this helps
Buzzz