using the census details and crime statistics from the net is a good start.

yellow pages tells you a lot about an area, from the comfort of your own home.

Also I expect asking others on this website about an area would get some form of response.

100k for sydney. I think you need to go maybe 300k-700k north or west to find something in that price bracket.

You also dont say whether your chasing +ve or -ve geared investments.