Hello,
Anyone remember dart master guy in BG1? He stands near Gnoll Fortress with his friend, smooth talker :) I found him really funny and cool (the dart master one) and decided to create my own dart master. I just want to go there and beat him one in one at darts! And be the best. And then kill Sarevok and Irenicus using only darts! I believe it's possible. So... now I must figured out how create that kind of guy. I'm not the best BG player, don't hve deepest knowledge, ancient cheat skills, any of those. So I'm asking for a little help. How should I build this hero? Maybe just pick simple warrior with darts and thats it? Or someone else is good for this role? Thanks!

The main problem with darts is that base ApR is set to 3 and only goes up from there. That means that you need a SHITLOAD of darts throughout the game. I don't think there's a returning dart in whole of BG1. Also they do little damage and the strength bonus is not applied on them. Would be fun if it did, but completely overpowered.
On the plus side the special darts (wounding and stunning) have quite strong secondary effects.

As for the class, you are correct that a simple warrior would be your best bet. Archers can not gain grandmastery in darts, only bows and xbows. A warrior could put 5 pips in darts and have a base ApR of 9/2, without any haste effects.
If you really want a kit, wizard slayer is your only choice and his miscast-on-hit ability would stack really fast on so many attacks per round. Although I think you need the tweak to apply miscast on ranged attacks, I'm not sure, never played one.

Thanks for the answer. So I will stick with the warrior idea. Number of darts probably will be a problem, in BG1 is no magic bags to store darts.

You can install bigger stacks teak from if you play normal BG1, or [url=http://www.gibberlings3.net/bg2tweaks/]BG2Tweaks if you are on EasyTutu/BGT.
I think that change is almost essential to make inventory management tolerable.