I've contacted him in another thread here, on opengameart, but he said he already has voice actors :) But in case he needs Russian/Ukrainian voice & translation, I'm ready :)

Looks like an interesting FOSS project.

Here's an example of my vocie acting in English: http://opengameart.org/content/voice-acting-sketch-open-dungeons

I don't know German well, but I believe I'll be able to preform a good pronounciation (I've been learning German for 8 years by now). So I'll need exact phrases (scenario) in German and some comments on mood, accents.

So I've got the ability to cut down all the man horurs when it comes to the keyboard.

But you speak of voice audio, not typing, right? I calculated the man-hours not considering the time for the script.

The script is explicitly on your part and it's a different topic. I speak of external work you'll require.

I can advice one simple thing. You make the game with text and leave voice acting chunk (i.e. like some generic biorgniorgnowrgw, or computer-synthesized voice). As soon as you have the game ready you post the request for free (or cheap) voice acting (here and on freegamedev, etc). If the people like your game, they might get involved, but be ready do do a lot on your part.

I.e. I'd love to voice act for a good & FOSS game, but this game should be getting somewhere nearer to betta, not just a raw idea (I have a raw 200-pages idea of my own :D). And this should be the game I like myself playing & voicing over. See here: http://forum.freegamedev.net/viewtopic.php?f=6&t=6145

P.S.

For a game like this will have nearly 50-60,000 lines of text because its a vast game.. 

That's gonna take up to 2000 A4s of text. Each A4 of text usually requires ~2 hours of work to record and process. I.e. you need about 5000 man-hours of voice acting plus audio processing, cutting, saving, packaging, etc. = 2 years of hard daily work. You really ask a lot :D