I am an official appraiser. The book is worth $29.99 USD. Where should I send the money?
Just kidding. You have a great book there. One place to start is ebay. There are 2 signed books currently for sale. One has 1 signature (Kip Wagner) and is at about $150. Another has all 8 signatures and the asking price is $275. I have little doubt both will be sold.
Looking at sold items on ebay with all signatures, in the past 2 months, one sold for $250 and another for $325.
Edit: On quick glance, the signatures on your book seem consistent with the others and are likely authentic although I'm far from an expert on handwriting analysis. I can hardly read my own writing!
Edit: I don't see a dustcover and the signs of wear will hold the value back a bit.
