I wanted to get beginner Windsurfing lessons in September, where is best for this. Can be anywhere in Australia, Bali or Thailand. And yes it needs to be September because thats what I want to do for my special birthday gift to myself. Thanks

Thanks

Wherever you do it, make it somewhere warm.
When you're learning you spend a lot of time in the water, rather than on it.
It's not loads of fun learning when it's so cold your fingers don't work properly.
That pretty much rules out most southern oz cities in September.

You could consider moving your birthday to December, jan, or feb, or march,... and that would make perth a really good place to learn.

There's a place that I believe teaches yeararound near Balmoral, Sydney.
Nice spot, plus gives you all of Sydney to go walkabout.

However September is a bit cold (not that much), and the wind is annoyingly offshore for learning at that spot..