The link you really want from MusicDSP is http://www.musicdsp.org/files/Audio-EQ-Cookbook.txt
I also recommend getting Lyon's Understanding Digital Signal Processing. I am a bit biased, though, since I was a reviewer for the second edition (but I think a third edition came out recently).
Also check out Digital Audio Signal Processing and DAFX:Digital Audio Effects, both by Udo Zölzer.
