Squarn's Junkyard was located on the planet Muugrah, close to the city of Slaibo, and was owned by the junk dealer Squarn. Sometime during the Galactic Civil War, a group of Rebels looking for spare parts to repair their hyperdrive landed here and were met by Klev who introduced them to Squarn. They hired a repulsorlift skiff and set about exploring the junkyard to find the pieces they needed. During this search they came across the astromech droid R2-D6 in a battle damaged Rebel Y-wing. Once they had freed him and bought him from Squarn they continued their search but were eventually attacked by a group of pirates also looking for Deesix. They managed to defeat this group thanks to the help of Squarn's mercenaries and soon left to deliver Deesix to a Rebel base.
Sources
"Buried Treasure" — Challenge 67 (First mentioned) (Unlicensed)