Wendy Higgins at Mortgage Choice in Glenelg comes highly recommended. She's a big time investor herself, so she walks the walk.
However, there's no reason your broker needs to be in your hometown. Mine is in Melbourne. All the work is done via email, phone and fax.
Also, there are some great and very savvy brokers here on the forum. Rolf Latham, for one. There are many others, too.