DIY centerpieces can be easy to do, and you are only limited by your imagination and checkbook. One thing that makes a cute centerpiece is a Blume Box. Check out their web site at http://www.blumebox.com.
Here are some other ideas for you to consider:
Click on the images to enlarge.
This centerpiece consists of 6 roses, river stone, and bear grass. It has clean, contemporary lines.
The candle grouping below, and to the right, features a crystal hanging from center vase, and roses glued to the top (bottom) of vase.
Below is a simple centerpiece of river rocks and gerbera daisies. Great for a cocktail table.
Below is a vase of wheat grass, surrounded by gerbera daisies on river rocks. Simple and clean.