j bomb - they just sit there and chat, sign books, sell books etc.
John Geirach has a separate reading in one of the theatres scheduled each day.
myself, i like to meet the anglers i've read about and read their books - so i can thank them for their contribution to our sport and generally congratulate them on a fine piece of writing.
i've been to maybe 8 or 9 of these shows and found these guys generally to be very humble, appreciative of the positive feedback and happy to chat or give tips/advice.
only once did i meet a complete rude A hole who shall remain nameless, but he did write a book on saltwater fly fishing, and after his lecture he had no interest in answering my questions or giving me advice after i hooked and lost 13 bonefish DIY fishing in the bahamas...
on the positive side, Ed Engle spent 45 minutes chatting with me on micro nymphs and difficult tailwater trout, and i shared a pint and cigarette with Alan Caolo where we traded NE sightfishing spots.
so generally, these guys genuinely love their sport and are pleased to see you - so don't be shy about saying hello.