You have very little choice here in Adelaide. You can go into the city in Grenfell St to Adelaide Optical Centre and get ripped off and ignored and mucked around with problems and wait 6 months after you've ordered it and it still isn't in yet.
Or you can go to Optic SA on Henley Beach Rd and talk to Andrew, who is reasonably intelligent and interested, pay a bit more and walk away with something.
Personally, I don't shop locally anymore, I generally buy from Bintel in Sydney and wait the few days for it to arrive. If you want some help, PM me and I can help you over the phone or in person. I am an active member of the Astronomical Society of Sth Australia, if that helps.
Cheers,
Gray.
