Nice to see those photographs! My Father was in 3rd Bn AIF, and wounded in the attack on Lone Pine, 8th August 1915. Who knows your Grandfather and my Pa might have met.
The Gallipoli Association is a fine band of brothers and sisters – the web site is a little out of date, but the Association is very vigorous:
http://www.gallipoli-association.org/
Regards,
SoG