| Steve Geddes |
It's usually written at the bottom of the credits page right at the front of the book (something like "First Printing, August 2010" or similar.
As it happens, my copy of the Inner Sea World Guide doesnt (it just says "Printed in China") but I dont have an update from 1st to later printings in my downloads. Paizo also generally provide the errata on each product's description page and there's nothing listed there for ISWG, so I'm pretty sure that means there hasnt been a second printing yet.
| Brian E. Harris |