Reddit reviews Chung Ta Noi: Conversational Vietnamese--An Intermediate Text

if you grew up in a vietnamese household and are even a little familiar with structure, you can just learn pronunciation and vocabulary and pick up a textbook. For pronunciation, there is a great flash application that allows you to listen to all the sounds and vowel combinations. For vocabulary, I have created an anki deck for beginners, intermediates, and advanced words. For a textbook, I'd recommend this book

If you are interested, I can share the program and anki deck with you.