Hi Ray,
In Perth you're pretty much limited to Binocular, Telescope and Optical Worls (BTOW) in Malaga.
www.btow.com.au.
Once a month they usually have a lunar/planetary viewing night where you can get a look through differnt scopes and ask some questions. Also AGWA holds their monthly meetings there (1st Tuesday of each month - although the October meeting may be different) and this can be a great place to ask questions.
BTOW also hosts 6 week courses cover astronomy in general and equipment (I did this prior to choosing my 1st scope, which by chance was a 8" dob) and a practical night at the AGWA/Starry nights observing area in Chittering.
Getting in touch with an astronomy club (I'm with AGWA) can be a great place to get a chance to look through different scopes and get some opinions prior to purchasing and I've found everyone more than willing to provide advice.
Cheers
Garin