Not sure when we got our first CD burner, but when we had this small Linux CD business in 1997-1998, they certainly weren't common where I lived. IIRC it started around the same time (probably got our first in 98 or 99). But at the beginning 'pressed' CDs were cheaper than CD-Rs and people who bought them also preferred purchasing 'real' CDs (CD-Rs had a reputation in the beginning of not being very reliable).