Dame Fanny Waterman

Just a brief word:

If you're just starting out with the piano, I recommend the Waterman/Harewood Piano Series (Faber Music).  The books are aimed at children, but if you're an adult the lessons are still the same so I would recommend buying them and dealing with the nursery rhymes about Kangaroos and whatnot. 

They are thorough and fun, well paced, and don't shy away from reminding you that it's better to get everything right, slowly, bit by bit, than to rush things through making mistakes and learning bad habits.

For more experienced pianists, I would recommend you buy "On Piano Teaching And Performance" by Fanny Waterman (also Faber Music).  An inspiring read by an inspiring woman.