The first thing to consider is the weight of the camera. The heavier the camera the sturdier the tripod should be. And the sturdier the tripod the more it will cost. But here are my recommendations:Â
1. The head must be fluid head.
2.  The head must have adjustment for pan drag and adjustment for tilt drag in addition to pan lock and tilt lock.
3. Choose a tripod with a floor spreader.
4. Choose a tripod without the centre column. That centre column does not belong to a professional tripod.
5. If you can, go to the store to buy the tripod. Look at the various models and then make a selection. Look for broken parts. The material of which present day tripods are made cracks very easily.
6. A good tripod is a necessity. No use having an expensive camera with a bad tripod. Spend some money to get something good. The brand doesn't matter too much. Personally I like Sachtler, Miller and Vinten. And do buy your tripod from a genuine Video/Camera store like B&H.  You can't get a decent tripod from Walmart, Radio Shack, Best Buy etc.Â
7. Finally make sure you get the quick mount adaptor which allows quick mounting of the camera, and don't forget the carrying case.