I made a set of Custom Brushes which are mostly tweaked variants and I posted a Youtube video on how to make a Photoshop style brush in Painter.
I apologize for my voice in these, but if people are interested I could do more of these videos explaining my custom brushes. Please let me know.
Video: http://www.youtube.com/watch?v=x2cvYNURsus
Currently my most used brush since Painter 12 is the Clumpy Brush modified because I have been doing portrait painting. I may post one up in my blog when I get the chance.
Anyways you can download the brushes here: http://qtmelon.studiokemono.net/paintertools/QTCustomBrushes.zip
Please note though if you have Painter 12 get the update. Brush management is sooooooooooo much better.
Just a small note, I do have a set of Painter 13 brushes I'm currently retweaking before releasing.