Bisexuality Support Group
Bisexuality is a sexual orientation which refers to the aesthetic, romantic, and/or sexual attraction of individuals to other individuals of both their own and the opposite gender or sex. Most bisexuals are not equally attracted to men and women, and may even shift between states of finding either sex exclusively attractive over the course of time.
I know for me I found dating site that focused only on women (no men and not an adult friend finder sex site) because I didn't know any women or the ones I knew were dating someone or I wasn't interested in. I met someone and we've been happily dating for almost two years now. Meeting someone online isn't for everyone but it is a nice way to meet people you would never have met before, which was my problem.
As for signs if a woman is gay or bi, there really isn't a signal we give off to each other, it's more a sense. Sometimes it's right sometimes it's not.
Hope that helped and good luck!