Many novels provide excellent accounts of this war. You can't beat Webb's Fields of Fire or Roth's Sand in the Wind. The 13th Valley has already been mentioned. For the Montangards, try Jonathan Raban's The Barking Deer.

David Elliot's massive (and expensive) 2 volume treatment of the war in the Mekong is definitive. Ward Just's To What End is often overlooked. I think it is every bit as good as Dispatches. The air war is not often dealt with. I like Thud Ridge, but I'm not really familiar with the literature on this aspect of the war, so others may have better suggestions.

Finally, there were two sides in this war. The material on the US side is enormous; on the NVA side, virtually non existent. Of course, there are many reasons for this--lack of access to archives, regime control of everything,etc. but there is a huge gap to any attempt to understand this conflict.