Great, a classic for vocal warm-ups I have used Vaccai as a young classical singer and then have references and taught out of it as a Voice Teacher for years. The exercises are more like small songs. Each "song" concentrates on developing a different part of the voice for example cadenzas, trills etc... They are not classic vocal warm ups. You need to warm up a bit before you attempt them. I would use them after a warm up and before singing through your repertoire. Check out:Vocalize!
about the ricordi edition In Italy Vaccaj's volume is available in a Ricordi edition edited by Mr Battaglia, but I guess and hope the real content, meaning the wonderful little arias, is just the same. First of all, unless you already have a clearly defined vocal range, I suggest you buy the edition for mezzo/baritone, whose range is really a medium one and is good for nearly every voice. Later on, you can buy the edition more suitable to your register. This small booklet is small in size only.
A beloved textbook, it... more info
An excellent systematical method for training the voice. The premise behind Vaccai's method is similar to that of the great Corri. While the latter tunes one's intervals through the correlation between various chords and the messa di voce, Vaccai composed short songs to guide the voice. Corri trains the voice; Vaccai leads one to sing, say, a trill, in the context of a song; and the end result is singing Verdi with ease.