Caloundra is one of my favourite places too. It's a pretty happening place with lots of chilled out cafes, bars, restaurants etc - and a stunning beach. But nowhere near as over the top as Surfers ...
Another fav of mine up that way is Noosa. I lived up on the Sunshine Coast for a few months late last year/earlier this year before coming down to Sydney, and the Noosa Surf Club was a regular spot for me - the view of the beach from up on the 1st level is incredible! Noosa def is a little bit more expensive, but there are affordable options if you keep your eyes open! I'd definitely recommend that you rent for a while after you land in Oz, dont rush into it, just so that you can sample a few different places and get a feel for each. You can try all the usual suspects: Stayz.com.au , AirBnB ...