There's a place called tybach that I was going to stay in once...but they ended up being booked.

It's a bit out of Fremantle but on their website they said it's very close to the bus service that comes every 10 minutes...

It's a very cool place at the back of someone's house...

Otherwise check out the websites of stayz and ozstays

They seem to have lots of different alternatives.

Cheers!