Mack's Cigar Shop on Sugarloaf Parkway in Duluth is just a little bit north of Norcross. But Clay's right, what looks like short mileage in Atlanta can take some time to navigate, especially at the wrong time of day.
Mack's has a good selection...AF, Tatueja, Gurkha, lots of Padron annis, lots of Rocky Patel, Ashton...I even succumbed to the hype and bought a couple of ESG there last week. He's not cheap though...paid $26.00 apiece for the ESG (which I'm trying not to think about).
Don't know much about Norcoss itself in the way of smoke shops.