Where can I learn a good technique of palming bills off a stack?
I didn't find sources for this.
I saw a really nice short change routine, that inspired me to learn about this.

I believe you are referring to Fred Kaps Currency Trick.

This is a very sought after booklet.

http://www.stevensmagic.com/shop/fred-kaps-currency-book/

Strange you ask this after watching a YouTube video, as there is no way you or anyone could know there is a steal in this routine as it is laid out to deceive this move.

Just an interesting observation of your question.

Thanks a lot.

I think of myself as a student of John Carney, even tough I never met him. A few month ago he taught Eddie Fechter's 8 to 12 in his online monthly course. That was basicly the first "counting" effect I ever liked.

Because of that I started exploring this "genre" of magic with different objects, including bills. Then I found a non official(I think?) video of him on youtube performing the short change routine. I think I watched that video 3 times every night for a month, I loved it. So elegant.