This used to be standard procedure for Betfair. I had to do it this looong ago, but I would have thought Betfair eveloved with the times. Guess not
These days OZ bookies just verify you online but if they can't verify you for some reason, this is the procedure they too will ask for, if you read the terms and conditions.
edit: probably the easiest way is just to get it done by Justice of the peace. No need to involve people you know
Most libraries (even local small ones) would have one sitting in, couple days a week.