"I Wanna Know" topped the Billboard year-end charts for Top R&B/Hip-Hop Singles & Tracks Airplay in 2000. Additionally "I Wanna Know" was ranked fourth on Billboard Hot 100's Year-End Charts making it one of Joe's highest finishes on the year end charts.
According to the song's co-producer Edwin "Tony" Nicholas, "I Wanna Know" was originally intended for Joe's previous album All That I Am. He removed the song from the final track listing due to taking issue with the label heads wanting to be involved in the creative process. A few years later, he was asked to contribute a song to a soundtrack and claimed he didn't have anything to send to the record label. He then sent in "I Wanna Know" because it happened to be lying around the studio.
A special remix of the song, entitled "The Roni Remix", can be found on a special U.K. edition of the album as a bonus track. The remix retains most of the original version's lyrics but features a different instrumental from its original as well as additional lyrics. Another Remix entitled "Phat Butt Remix" by Beau "Dj Bo" van Gils is made in the "2Bro'z" Boomroll Studio's in roermond The Netherlands, additional raps are also done by DJ BO. This remix is released on vinyl 12 inch and as bonustrack on the album.
The music video (directed by Bille Woodruff) starts out with a woman (played by Claudia Jordan) having an argument with her boyfriend in an alley off the street. Joe and two of his friends see the ongoing argument and after the woman's boyfriend leaves he approaches her and talks to her, in the process of obtaining her phone number. The rest of the music video shows Joe and the woman spending time with each other as their relationship becomes stronger. The woman is assumed to have cut off her relationship with her boyfriend from the beginning of the music video.