So this page was a screentone test in photoshop. I have tried and tried and tried but something always went wrong. Turns out it was a really simple issue. Anyway I worked in A5 600dpi greyscale mode. I used colour halftone to make the screentones and filters>> pixilate>> Mezzotint or noise for the texture on the lips. Character is a guy, don't ask.
Basically I painted, I wasn't worried about being neat, shadows and all on one layer under the line art and used colourhalftone and when that didn't work I used a plugin that makes better tones but I found if the image was huge with a high res of 300, 600 or 1200dpi (1200 has an amazing range) then I found it was more than possible and I got some nice results