Have you seen any episodes of "What not to wear", with Trini and Sussanah?
They also have a book out, same name, which is good on how to get the best results if you have a small/big bust, no hips, short/long legs etc. They point out which colours can make you look smaller or larger, that sort of thing.
I have found the magazine "In Style" gives a good guide to combinations that work, as well as upcoming trends. At the moment layering is very in, the longer layers underneath of course.
To avoid having to update my wardrobe too much I have tended to go for styles that don't date, rather than the latest fashion. For example I have two coats I am wearing at the moment. One is a light blue sheepskin and the other is a full length black leather number. Neither of those will go out of style. The same with denim and leather skirts, and calf length boots.
If you can pick some celebrity whose style clicks with you, you can try copying their general look, and adjust as neccessary. Mine is Emma Peel from the 60's TV series "The Avengers". Diana Rigg set a style that will never date. Also I am a big fan of the Mod look of the 60's which is always making a comeback. Main thing is, as in everything else, be yourself.
Karen.