"Comics and Sequential Art" wasted too much page time with reprints of Eisner work that I had already seen. I know it's a classic, but it didn't really help me much and I wanted my $24.99 back.
"Understanding Comics" and it's sequel "Making Comics" are much better, IMO.
Though honestly, there is no substitute for studying other artists work in detail. Get a lot of various graphic novels and pay close attention to how they open, close, arrange panels and word balloons, ect.
"Since God created man, and man
created the Transformers, the Transformers are like a gift from God!"