There is no VOCALOID video game, unless you're referring to MMD (Miku Miku Dance), which is completely free on VPVP.
No, Vocaloid is not an anime. Vocaloid is a singing voice synthesizer software that allows users to create songs and vocals using virtual characters. However, Vocaloid characters have been featured in various anime and manga series.
Yamaha created and developed the Vocaloid technology. See the Vocaloid wiki article for more details about the technology and its impact on the internet.
If you're talking about the Japanese vocaloid then you can't. But there are several ways to change vocaloid into English once you have it. Like in this video for example: http://www.youtube.com/watch?v=D01vaheD-Oc
Vocaloid made a music video like that, you can find it on youtube. If, you type in kurruto Odotte Ikkaiten; just scroll down and you'll see it.
Vocaloid is not a person or a group that you could write messages to. It is a singing synthesizer technology used in many software products also called a Vocaloid. Vocaloid, at its core, is an instrument, like a piano, or guitar. No one person or group controls the music and music videos you see on the Internet. The popularity of Vocaloid is driven by its users and fans. Anyone can purchase a Vocaloid and start creating songs with it.
Yes. Only since she stars in one song with Snow Miku from the actual creator of Vocaloid from a music video. If you type in "Vocaloid", though, she won't pop up with the band...she is basically just Hatsune Miku transformed!
Yes, Ai is a vocaloid. A vocaloid 3 to be exact.
Teto's character item is, apparently, french bread. Note that Teto Kasane is not a Vocaloid, but an Utauloid for the free singing synthesizer UTAU. Since the Vocaloid and UTAU communities are closely related, Teto and other UTAUloids have many fans within the Vocaloid community and its not surprising to see many songs featuring Teto or other UTAUloids singing alongside their Vocaloid counterparts.
Vocaloid fans like Vocaloid. Vocaloid fans are located around the world. Vocaloid fans also have a tendency to like Japanese animation (anime) and comics (manga).
Piko is the name of both the Vocaloid and the voice provider, who is naturally not a Vocaloid.
No Teto is not a Vocaloid. I have heard before that She was made to be a prank. She is mistaken to be a Vocaloid. She sounds like a Vocaloid(y) software.