Ron Ewing 6 string dulcimette songs
It's true that 6 String Dulcimer group hasn't been too active recently, but remember that you have to actually join a group to see the responses to all the discussions.
I'm sure there are as many responses to this question as there are personal musical styles, but I'm happy to chime in, not with specific song suggestions, but with types of songs and techniques that might be useful.
There are two different attributes to your dulcimer that might suggest special consideration. First, it is an octave instrument. You can play the same tab as everyone else but will be one octave higher. Sometimes, you don't have to do anything special and will blend really well. I sometimes take my dulcimette to my monthly dulcimer club and pull it out when we play Southwind, for example. My dulcimer really stands out from and complements the rest because of the higher register. But that higher register--and the shorter VSL that allows it--also means that the instrument has less sustain. The strings just stop ringing (or get really soft) much faster than those of a standard dulcimer. So one trick is just to play tunes that have lots of notes. I actually find it easier to play fast fiddle tunes on my smaller dulcimers. But if you choose tunes with half notes and whole notes, you will want to play a lot of arpeggios, basically playing chords one string at a time to fill in the spaces in the melody. To see what I mean about using arpeggios to fill in the spaces, check out the version of Raisins and Almonds I posted a while back.
But your dulcimer is also a six-string dulcimer. I have a six-string baritone dulcimette, and tend to play songs with a lot of strumming. Fingerpicking doesn't work as well, but fast strumming is really fun with all those double strings. Think of the rhythmic role of a mandolin in a bluegrass band. Remember, however, that you can also take off the extra strings and have a 3-string instrument. My baritone dulcimette is currently strung only with three strings and is nice for softer, quieter tunes. In a sense, you have two instruments in one.
Good luck. I'm sure you'll find a bunch of tunes and develop your own style of playing them, something unique to you and your dulcimer.