Below are some useful links to the laws of the game as well as the advice to referees, among other information – including game report information (where to send reports can be found on Arbiter). For example, some leagues expect game reports to be submitted through their league website while some leagues expect emailed game reports.
Note: This PDF also has helpful information on submitting game reports. Between this and the Arbiter home page details should be attainable!
Laws of the game
Referee administrative materials
USSF advice and position papers