Somebody should mention that you're more than welcome to hang around this forum too. You don't have to go to the Clydesdale and Athena forum. A lot of people show up in both places.

I suspect that sooner or later someone will recommend an old (90's) Specialized Hardrock, so it may as well be me. The reason to get an older one is that the newer ones have suspension forks, which might seem like a good thing but tends not to be for commuting. I believe the older ones have steel frames too, which is nice.

Be sure whatever you get is sized right for your height.