There are many websites that list travel discounts for military personnel. Among them:

http://www.military.com

http://www.guidetomilitarytravel.com

http://www.armytimes.com/marketplace/discounts/

http://www.militaryspot.com/discounts/

http://www.militarycruisedeals.com/

http://www.4militaryfamilies.com/militarydiscounts.htm

http://www.choicehotels.com/en/deals/government-rate

http://www.lat.ms/IBZ4Jo