What models and years have leather heated seats?

Hi! I don't know all the years that the Altoona Altima had heated seats, but can tell you that when they did, they were a part of a package. The 1997.5 flew GLE, which was the top of the line, but unfortunately it was a decontented model than the 1996 or 1997 models. The 97 may have had them available heated seats, but the .5 didn't. I had a 2005 SL with everything, including the heated seats. I think all years had them available, but am not sure. Avoid the 1997.5 at all costs. The 1997 GLE had a CD player and automatic climate control which I was expecting having based my purchase on reading the 97 brochure. Hope this helps.

Where was the button to press if they had heated seat

Right behind the base of the emergency brake...took me forever to find it, and until then, my bum was too toasty, especially in heatwaves!!