katykrunch if you have found your grt grandmothers name, DOB and where she lived, then the census records are your next port of call, from there you might find her with her whole family also age and place of birth, from there you can work back, however I have hit a couple of brick walls where people seem to have disappeared, also my Grandfather has no fathers name on his birth certificate and when his mother remarried he took her new husbands surname, so I was looking for the incorrect surname.
I had to trawl through an awful lots of census returns and BMD results to find him, his birth certificate proved my findings, but they were only £7 or so to buy back in the day.
I have an Ancestry subscription and they have enormous amounts of information, but I started of with the free LDS sight and found records of my family, then I went back to Ancestry and found the census returns.
But I will never get my Grandfathers paternal side of the tree. That’s how it goes I’m afraid.