Sitars don't have "the frets above the strings", 'cause then how could you fret them? If you couldn't fret them, why would they have frets?
They have extra strings, below the frets. These are not the main strings, they are "sympathetic strings". The playing strings are above the frets, and I believe the drone strings are as well.
Here is a sitar, with sympathetic strings below the frets:

Then of course there's electric sitars, which are really just an electric guitar with added sympathetic/drone strings:

EDIT: Damn, PhotoBucket really shrunk the images. If you want bigger pictures, here's where I got them from:
http://www.alchemystudio.it/Strumenti/Sitar.htmhttp://www.umenaka.com/syasin/syasin/Jerry Jones SITAR.50.jpgGive me a Conklin black, gold and cream double-neck bass, with seven strings on each neck, one neck fretted and the other fretless.