If it is Duels, keep tabs on this thread:
How to duel - MONDAY 17TH 19:00 GMT | Movie Battles II Community
With basics from agentoo8, you can build on and on those foundations. EU Duel Server has a lot of guys, who like to teach newcomers.
I can't talk about the US side, but I have seen guys from the USA attended agent's sessions.
Also, forums offer some threads related to Dueling and using saber in the fight. Like this one:
[Guide] The Dueling Compendium | Movie Battles II Community
If you need to get a grip on saberist in the open, play gunner classes first. I know it's tempting to get into saberist class right away, since it's the unique thing in this mod, but getting to know all the classes might help how to fight Jedi/Sith and vice-versa. You can use that knowledge then from the other side, because you got to know weaknesses of gunner classes and you know, how to approach it with melee class like Jedi/Sith. Don't forget also, that Jedi is a support class.
Community can help, if you bump into decent behaving players. Some are trolls though, that's completely normal in every multiplayer game though.