David Scott Stone

This guy was a touring guitarist in 2000 and 2001 plus he did some extra dates with the FantomasMelvins bigband during other years, he appears on the Bigband album Millennium Monsterworks, and he also did some stuff on Hostile Ambient Takeover and Honky.

He's also been involved in many other bands such as:

Get Hustle
He played guitar in this band, their release Earth Odyssey features him and is probably the recording which showcases his talent best of all.  This band also featured Buzz's wife Mackie Osborne on bass for some of their recordings.  Shortly after the release of Earth Odyssey he left the band, this is when he joined the Melvins for the 2x4 tour of 2000.

Axe The Reaction
Don't know anything about this band

Gashley Snub
This band also included Dale Crover and Mackie Osborne(Buzz's Wife)
They released a song on a compilation KRS100 A Slice of Lemon 2CD/2LP

Slug
I honestly don't know anything about this band but I beleive this was his main band prior to being in Get Hustle.  I beleive he played guitar and that the band was actually pretty good.  All of their releases are out of print though.

Unwound
He toured as a second guitarist with this band on their Leaves Turn Inside You tour
Here's what he had to say about the band:
Unwound seeped into my life sitting on a couch at cleaning time at the Jabberjaw one evening in LA. I remember listening to Fake Train as Gary Dent would be sweeping up the place, I had asked him several times about it but couldn't manage to remember who it was. It was after some sort of early 90's Am Rep sort of show, I was beat serving espressos to the long shorts/shaved head crowd and was sitting in the TV room eyes shut. The room was clearing, and as it did I could hear the first side of it come into focus, the end of Lucky Acid into Nervous Energy, and then the "medley" that closes the first side. I was freaked out so much I couldn't move! It was mesmerizing. I got up and rewound the first side to hear it again now that it was only Gary, Jessie(our friend) and I left in the place. My life had changed at that moment.
Somethings:
---A show in Pomona/Claremont(where was that one again Vern?) with Fluf. Unwound so good I couldn't do my own band anymore. Unwound's Mountain Dew days.
---Unwound in Austin Texas sandwiched between Polvo and Sonic Youth. WASTING everyone that night. 5000 kids jumping up and down to Dragnalus, David U and I trying to play Hexenzsene back at his place. Going out with them for potato taco's the next morning. Jamie Spidle, and I contemplating going to Dallas to see them again that night.
---Countless Jabberjaw shows including the one with Justin's famous "Jesus Christ Pose" photo op. Slug getting on a bill(w/Clikitat Ikitowi). Valley rednecks with half shirts and beer guts dancing behind Sara the whole set !!!scary!!! really this goes on, and on...
---Hearing all the new songs off of "Challenge For..." the day before Halloween, and Unwound, Witchypoo playing a show with Get Hustle that night at the Midnight Sun. Sara with mallets! Vern's bass lines, Justin becomes angular... what was hardcore again???
---Playing guitar with Unwound in Atlanta at the Echo Fall 2001 a week after the world went crazy. Thrones, Mecca Normal and us playing Black Flag, Germs, and Sex Pistols covers together onstage.
---many more...