Delta and most domestic U.S. Airlines are now charging for checked luggage.

Luggage fees are calculated and collected at check in. Some carriers allow luggage to be checked in online at a reduced fee. Please check the web site of your carrier for up to date luggage policies prior to departure.

http://www.delta.com/traveling_checkin/baggage/index.jsp

http://www.suncountry.com/hometools/helpBaggage.shtml

http://www.united.com/page/middlepage/0,6823,1031,00.html?navSource=Dropdown07&linkTitle=baggage

http://www.aa.com/i18n/travelInformation/baggage/generalInfo.jsp?anchorEvent=false&from=Nav

http://www.continental.com/web/en-US/content/travel/baggage/default.aspx 

Carry on luggage is restricted to each airlines policy and several airlines will charge a penalty for passengers who try to carry on more than their allowed limits.

Oversized and excess bags will have additional costs.