The Wilson sisters - Nancy and Anne Wilson from Heart. Nancy's the guitarist.
Heart are probably from before your time but worth listening into.
Ash are very much current (have been around for about 10 years). Charlotte's good.
Kaki King is considered one of the best guitrarist going round.
Miki Berenyi and Emma Anderson from Lush were pretty good, as was Jodi Phillis from The Clouds and Suzie Higgie from The Falling Joys.