[hyl]

Elina is just voiced by Shimizu Ai (under a psuedonym), anyone can hear that >_>

As for the other more well known seiyuu in dracu riot

Nikola: Nabatame Hitomi
Miu: Taguchi Hiroko. Who is known for voicng Sora in Yosuga no Sora, Yutsuki in Mashiroiro Symphony Mutssu no Hana, Miyako in Ef and many other VN's
Azusa: Nanjo Yoshino, who is probably more well known for being the current lead vocalist of the Fripside (who also did the 2nd opening of Hatsuyuki Sakura: Hesitation Snow)

edit:
For these seiyuu's i didn't even need to look up, because they are very easily distinguishable for me.

edit to balzac:
Dracu-Riot felt less worth for my money than Hatsuyuki Sakura. While Dracu-Riot is not a bad VN , it did not live up to the hype that it got almost 6 months before it's release. Also Dracu-Riot costed me 1000 yen more than HatsuSaku and my bonus item was just a stupid book or telephone card....