After a lengthy absence, I've returned to offer what I consider to be two of the finest and most concise instructional documents concerning role playing one can locate on the entirety of the internet. Constructed over the span of ten or so pages, the eminent Greg Stolze supplies the reader with a 'crash course' in the art of tabletop gaming etiquette through of a combination of informative text and hypothetical scenarios (no pictures, sorry). Said reader may find one or both of the documents to be of use, as they each address one of the two main roles of roleplaying: player and Host. With this approach, each unique consideration and pitfall of a specific role may be addressed and elaborated upon, giving a full (yet thankfully brief), set of guidelines for each party. In any case, I currently have the player-centered version on my 'required reading list' for those who wish to join a session.
For the Host: gregstolze.com/HowtoRun.zip
For the Player: gregstolze.com/HowtoPlay.zip
More on the Author: en.wikipedia.org/wiki/Greg_Stolze