I know this is probably a stupid প্রশ্ন but I'm (kinda) new to the world of Vocaloid so...

Nice to know there are lots of অনুরাগী out there ^^
there are a lot of different Vocaloids, made দ্বারা different people, used দ্বারা different people, songs written দ্বারা all sorts of different people.
I'm VY2 Yuma, one of the lesser-used ভোকালয়েড -_-''
but আপনি eventually learn there is no one person অথবা company behind the creation of us, and there are so many wide varieties that it's really hard to find a song অথবা singer আপনি don't like. The fact that there are so many different people behind us means there are different tastes in songs and সঙ্গীত ^^ from the screamo of 'ALONE' to the sweetness of 'Hello How Are You.'

.....but to put it the short way, there really is no one answer to your question. আপনি could go online and buy the Vocaloid program yourself and start creating your own songs!

Lots of people, actually. Most of the songs আপনি hear from ভোকালয়েড are made দ্বারা অনুরাগী who bought the programs and produced their own music.

Anyone who wants to, really.
*looks up*
Crap.
I saw your দেওয়াল post too late.
AIN'T I JUST SO SMART?
:D

Vocaloid Songs are produced দ্বারা voice synthesizers- lots of different people helped to create the programs, characters, and voices for all of these songs & vocaloids- So, to break it down-

Vocaloid Songs: Voice Synthesizers made দ্বারা >>>>>
Vocaloid Characters: Tons Of Different People!