People vary dramatically in their reactions to being photographed in public. My main advice is that if you are close to the woman, be prepared to duck. In the US, photographing people in public is legal as long as you are not harrassing them, but many people have opinions to the contrary.

One of the world's most famous photographers, Garry Winogrand, published an entire book of street shots of women (generally not long hair back in those days, though). Look at the prices:

amazon.com/gp/product/offer-listing/0374513015//103-5801482-8473451?condition=all