Hi Letigre,
Sounds like you are about to really enjoy yourself with this gear.
The diagram below shows the defacto 5.1 speaker layout. Sometimes, you have to do what you can to accommodate odd room shapes and such but this would be the ideal angles for you to start with and tweak from there.
This picture came from an excellent guide to HT layouts provided in the "Articles" section on the Axiom home page. Lot's of good info there on everything from beginner to rather advanced topics.
Axiom Learning Center
