You're in luck! We have entered into what I believe will be a golden age for material written by the Vietnamese, both Northern and Southern on their experiences during the war.

In 1983, WGBH for PBS produced Vietnam: A Television History, which had the benefit of being filmed soon enough following the war that they were able to interview a great deal of policymakers and decision-makers. Additionally, they were able to interview a great deal of South Vietnamese and North Vietnamese about their experiences, though at this point in time, the North Vietnamese were not as open about their own foibles and shortcomings as they would be in the recent Ken Burns documentary.

I highly recommend browsing their vault of interviews if video media is an avenue you'd be interested in. The transcripts aren't great, however.

The Vietnam Center and Archive at Texas Tech University is probably the single largest repository of documents and stories from the Vietnam War, much of which is from the Southern Vietnamese perspective. They span the entirety of the war but the search function isn't great, so you may feel a little overwhelmed trying to find specific things.

Now in terms of books, there is also a great deal of memoirs being published, on essentially every facet of the conflict by the South Vietnamese perspective, with more and more personal narrative and memoirs being written by the North Vietnamese (much of the post-war North Vietnamese literature focused on battle analysis, rather than personal experiences). The sky is sort of the limit here, so if you have any particular interest in certain aspects or perspectives, I'd be more than happy to give recommendations, but a few of my favorites are:

North Vietnamese

• From Enemy to Friend: A North Vietnamese Perspective on the War by Bui Tin (who also wrote Following Ho Chi Minh: Memoirs of a North Vietnamese Colonel)
• A Vietcong Memoir: An Inside Account of the Vietnam War and Its Aftermath by Truong Nhu Tang
• No Other Road to Take: The Memoirs of Mrs. Nguyen Thi Dinh by Nguyen Thi Dinh
• Last Night I Dreamed of Peace: The Diary of Dang Thuy Tram by Dang Thuy Tram

South Vietnamese

• Returns of War: South Vietnam and the Price of Refugee Memory by Long T. Bui
• In the Jaws of History by Bui Diem
• Ship of Fate: Memoir of a Vietnamese Repatriate by Tru Dinh Tran
• Voices from the Second Republic of South Vietnam (1967–1975) edited by K.W. Taylor
• Counterpart: A South Vietnamese Naval Officer's War by Kiem Do

Non-Aligned Civilian

• Mourning Headband for Hue: An Account of the Battle for Hue, Vietnam 1968 by Nha Ca
• The Sacred Willow: Four Generations in the Life of a Vietnamese Family by Duong Van Mai Elliott

I've stuck with non-fiction, non-anthology, and non-academic analysis for this short list, so do feel free to ask if you want any suggestions for those as well.