Below are links to documents that may help you in deciphering the laws surrounding some tricky areas.

General Principles of Refereeing (PPT)

The Kickoff (PPT)

Scrummaging (PPT)

Lineouts (PPT)

Offsides (PPT)

Advantage (PPT)

Sevens Guidelines (Word)

Laws of the Game (This is a zip file containing PDFs of all the laws)