Whenever you want to change the style of any part of the theme, use Chrome or Firefox+Firebug and right click on the area you want to change and choose Inspect Element. That will bring up a console that shows exactly which lines of CSS in exactly which files affect that element so that you can go in and change the style how you see fit.As for turkish characters, try turning on the various font subsets in the theme options >> style tab becasue by default it only loads standard characters
I agree that using Inspect Element might provide a solution, but one would have to manually dig into css for each and every element that needs to be changed. Settings in theme options should be enough for a user to change all fonts used in the theme without going into css manually, which I believe could be covered with an update.
I see what you're saying, I'll consider that for a future theme update. I agree it would be better to have more control over font changing within the theme options, thanks.