You also have to remember that the porno world would have you believe that the female ejaculates like a faucet. Now I have actually seen two women who did ejaculated 'a lot', most women just get very wet and often will not differentiate this from normal lubrication. There are porno''s where women will fill the vaginas with water and expel it using the vaginal muscles to simulate a large ejaculation.
Yes..generally the gspot orgasm is the catalyst for 'squirting'. If you look up the "skene's glands", you will find information that may help you understand the mechanism behind female ejaculation.
SOME women have the ability to squirt when they are having an orgasm, females do "ejaculate" though it obviously isn't the same thing as a man ejaculating.
From what I have heard it is caused by stimulating her G-spot.