Music like Dave Matthews Band
This is a tough question, because no bands really sound like Dave Matthews Band. I understand your struggle; every time I create a DMB Pandora station, I have to listen to 20 or so other 90's alternative bands who DMB could play circles around.
If you want a band that sounds just like them (i.e. violin, horns, croaky lead singer on an acoustic guitar), you may as well just stick with DMB. However, if you're interested in a few bands that manage some of the essential traits of DMB, see below:
Intensity is a critical trait of Dave Matthews Band music. I can't think of anyone off-hand who can get behind a song the way Dave can. However, here are a few honorable mentions in the category:
Mumford & Sons
Any musician that has tried to cover DMB can tell you that the songs are far from simple. Multiple parts, mood changes, and tempo switches keep us on our toes while listening to their music. Here are a few bands that are in the same boat:
Edward Sharpe and the Magnetting Zeros
Acousticness (yes, I am aware this isn't an adjective):
Dave plays an acoustic guitar like no one else. It's an extension of him that is more of a limb than an instrument. Here's a few artists who are capable of similar achievement:
Most of these bands/artists will not fill you with nostalgia of your last DMB concert upon listening. They may, however, do something more valuable: expand your horizons within your predefined taste. Enjoy and please let me know what you like/don't like.