There's not much difference between a man and a womans pack. alot of brands have unisex models. The main difference is usually the shoulder straps (a bit more curved for those well endowed women) and sometimes in the hip straps.
If your on the small size i would suggest avoiding the large 70L packs, (u dont want to be carrying that much weight)
The best thing to do is go to a store (or several) and try on the different brands, dont look at prices but find which brands fit you the most comfortably.
hope that helps.
And enjoy the shopping.