First post

I haven't owned a bike in a very long time and was looking at getting soon for the short commute to the gym from home. At the same time I wanted to move cardio exercise outdoors and give mtb trails a go (novice/beginner runs). Can you guys recommend me a bike under $1000 and maybe a few bike shops in Syd I should check out? Something capable offroad but still alright for commuting. One bike I was recommend was a Trek 4500 - anyone have feedback on these? Once again, I'm a total noob so feedback, info, opinions would be appreciated

Cheers
Chris