Customs and Courtesies and Traditions of the U.S. Army- http://www.uwosh.edu/departments/military_science/class/tsp_158-1181.html
This section describes some of the most common military customs and courtesies you should follow:

FM 22-5 Drill and Ceremonies - http://www.adtdl.army.mil/cgi-bin/atdl.dll/fm/22.5/toc.htm

AR 840-10 Flags, Guidons, Streamers, Tabards, Automobile and Aircraft Plates - http://www.geocities.com/tthor.geo/840-10.html

DA Pam 600-60 Customs and Courtesies - http://www.usapa.army.mil/pdffiles/p600_60.pdf

AR 840-1 Department of the Army Seal and Department of Army Emblem and Branch of Services Plaques - http://www.usapa.army.mil/pdffiles/r840_1.pdf

AR 600-25 Salutes, Honors and Visits of Courtesy - http://www.usapa.army.mil/pdffiles/r600_25.pdf

Everything You Ever Wanted to Know About  Military Customs and Courtesies - http://freepages.military.rootsweb.com/~rootsrus/Customs.html

Army Family Team Building Customs and Courtesies - http://www.gordon.army.mil/aftb/customs.htm

US Army Online Promotion Study Guide - Customs and Courtesies - http://www.military-net.com/education/mpdcustoms.html

ArmyStudyGuide.com - Military Customs and Courtesies - http://www.armystudyguide.com/milcustandcourt.htm