Regardless of what you may think of Carroll's motives, they are great books written very well. There are many quotes to extract.
I recommend getting The Annotated Alice ISBN 0-517-18920-8 (alternate, search). The margin notes lead to wider understandings of the works that would otherwise be lost on us over a century after their original publishings.
See also Glibert Adair's book Alice Through the Needle's Eye (alas, out of print), an entertaining book very much in the spirit of Lewis Carroll.
See also the AlicePlugin.
Let it be known, that I have not enjoyed reading Alice in Wonderland. It bored the hell out of me. It felt like there was either humor too simple for me to enjoy or too subtle for me to appreciate. I like references to Alice in Wonderland when it comes to quantum physics and other things, but reading the real thing was too much. I got up to the tea party and the mad hatter before I quit. --AlexSchroeder