You can get fully furnished holiday type short term lets in Brisbane abs surrounds, we found lots via Booking.com and often if you contact the landlord or property manager and tell them you want a month they will discount, we rented for a month in Gold Coast before securing a long term rental, it gave us a chance to see areas, get jobs, schools all sorted...it's a bit more expensive but you'll have all you need, Internet etc and could save you renting something you don't like. When you do find a long term rental we found that if you have rental references from the UK, your visa and your offer of employment you can rent without putting advance rent down. Short term gives you a chance to settle and make sure you are happy before getting everything shipped too.
The rental agents have all been good, I worked in rentals in the UK and the Aussie system is more laid back, one thing that's a bonus here is the landlord pays the rates/council tax so one less bill!
Good luck and Brisbane is great, we've been here since 31/07 and have found everyone friendly and it's been a good experience, a few issues but nothing that wasn't sortable, and these forums are great!