Modern American Poetry - This site has several excellent articles explain the Vietnam war from several angles.
PBS- Battlefield: Vietnam- This site is produced in conjunction with the PBS documentary on the Vietnam War.
PBS- Vietnam: Online- This site parallels the American Experience TV series Vietnam: A Television History.
The Wars for Viet Nam: 1945-1975
American Radio Works
The History Place- Created by Philip Gavin.
History.com- From A&E History Channel
The Vietnam Center and Archives
15th Field Artillery Regiment Website- Very Military oriented site but interesting and good timeline.
The Vietnam Veterans Memorial