It's actually a chord mainly used in jazz,and for the purposes of most songs D7 will do adequately instead

To get it on a guitar-


With your index finger make a barre over the D,G,B, E strings under the fourth fret.

With the second finger make a second barre over the G, B and E strings just above the other barre below the fifth fret.

Bring your thumb around and barre the bass E and A strings under the fifth fret.

This, in effect, means that all the strings are barred under the fifth, except the D which is barred under the fourth.

Hope this explians it but it's a bit difficult to describe it verbally.

There are other jazzy ways of doing the chord, but this has the advantage that it is slideble, and once you can do the shape, you can get any ninth chord.