is there a 35mm equivalent lens for the Nikon D80??

Answer 1

Compared to film bodies, the D80 and all other Nikon dSLR cameras have a 1.5 focal length multiplier. So, to achieve a 35mm field of view, you'd have to use a 35mm/1.5 = 23.3mm lens.
Nikon has a 24mm f/2.8 lens ($300 retail). You coud also just set your zoom lens to 23mm.
(At least I think that's what you're asking.)