Grammar
William E Welmers’ A Grammar of Vai – the latest grammar analysis made of the Vai language.
Syllabary
The Unicode specifications, with full syllabary table (pdf)
SIL’s proposal for encoding Vai into Unicode, with phonetic pronunciation (pdf)
Examples of writing
The story of The Rascal Man (though badly translated to English)
Excerpt of an old manuscript (jpg), photo by the British Museum