Hi,
Im looking for a place for a 1-2 weeks trip focused only on windsurfing. Finally planning to take time off the day to day work and hopefully once and for all....spend time on improving my windsurfing, after years surfing on and off without much consistency or technical improvements. Any suggestions? When?: june. Destination? Prefer close to home, VIC, however open for travel suggestions in AU or overseas. Instructor / coaching? Yes, even if part of the time.

Wait until november and come to wa.

agreed
and if coming around the time of the LOC guy crib has been running a course the last few years.

June, Maui, consistent wind, warm water, the surf is small, don't even have to get into the surf if you don't want. Plenty of great instruction and rental stuff, worth the money, you'll return a much better windsurfer, w/o question. Lessons and an experience that will last you for the rest of your life, and you'll be going back for more, guaranteed.

Thx! Any special beach / company to to contact there?

You could email Matt Pritchard for starters, he runs instructions as do many others.
Many here have done this, Yuppy comes to mind, he had a great time.
You'll be sailing at Kanaha Beach, it's close to the airport and all the shops.
The shops are numerous, High Tech, Hot Sails Maui, Second Wind, Hawaiian Island Windsurfing, just for starters, most have lessons as well as great equipment. Do a Google search (Maui windsurfing shops), you'll find more than you need.