Got to read about sage Lomasa here while researching about Kamyaka Forest:
The Pandavas came back from the Dwaita woods to Kamyaka again for a 2nd time. This time they lived without Arjuna who had left for military training in the northern Himalayas (3,36). They lived thus for 5 years in Kamyaka (3,50). Ghatotkacha lived with them during this period (7,181). Sage Vyasa and Sage Lomasa visited them then. From there, they set out for a pilgrimage across India, guided by Lomasa (3,93).
But want to know more about him, coz he belongs to the same era to which Ved Vyasa belonged. Are there any known works by him?