Not bad for a first try. There are lots of little things you can do to increase your sharpness. All of them minor but they add up quickly. One thing that is most important is a sturdy tripod. The other is to utilize your exposure delay settings (put at 3 sec or the highest possible setting) and if you have a remote shutter release, that's even better but I would still use the exposure delay.
And then as Scott is hinting at, during your PP be sure to play around with the sharpening levels. A little bit goes a long way. Too sharp and it will start looking grainy so play around with it.
All in all, a great first try. I can tell you it's 10x better than my first attempt, that's for sure.