i've had a similar experience in that i don't find NC shades fit me that well...but nw is generally not quite right either. i've been colour matched most often with nc shades, but once with nw (when i was at my palest)
every time i've been foundation matched, i very soon find that the shade doesn't look quite right. my skin tans considerably in the summer, when nc45 fits well, but in the fall/winter, it's way too dark and orange. and nc 42 is too light and peachy. it might be that i one of those missing shades that are available in india might be a good fit, but none of the mac shades i've tried are doing the trick at the moment.
in terms of knowing whether i'm warm, cool or neutral - i don't have a clue! gold looks MUCH better than silver does on me, but cool shades like blue pinks etc look better on me than peachy ones.
at the moment i'm testing out a couple of nars foundations, and i wasn't sure whether i should go with matching to my neck or face. on my skin they are actually only subtly different, but i find the shade that matches my neck makes me look a little washed out. the one that matches my face is slightly darker than my neck, but i think it looks better because i don't look tired. i know that the 'rule' is to not look a different colour on your neck than your face, but i think i'd agree with kimbunny - go with what looks most flattering/you feel most comfortable in!