Currently this is all i was able to find, but it is more than enough for start:

Basic video tutorials by Bob Shrader (OldRadioGuy):
https://www.youtube.com/channel/UCb7Etr ... shelf_id=0

What's new in Version... (very nice illustrated explanations for every new tool in each version):
https://www.pl32.com/pages/rnote.php

PhotoLine Official Manual:
http://www.pl32.com/plbin/manual.zip

PhotoLine Un-Official Reference Guide by evrencomert:
http://evrencomert.com/PhotoLine.htm

An Introduction to Photo Editing with PhotoLine by Russell W. Cottrell:
http://www.russellcottrell.com/photo/PhotoLine/