useful books:

computer music tutorial	overview of all aspects of computer music (signal generation, effects, sequencing, popular hardware and software, MIDI, etc) written by curtis roads
scientists and engineer's guide to DSP	free and engaging overview of DSP.
musical applications of microprocessors	out of print, out of date (published in the 80s), but still incredibly enlightening. i think i found mine at bookfinder.

other DSP links:

the DSP music syndicate	collaberative DSP music effort between myself and 3 people a part of (or soon to be a part of) the MIT media lab
shifty/noah	crazed genius overlord of DSP on the ADSP-218x processors. made a MIDI synthesizer from the ADSP-2181 EZ-Kit, and developer of many unique and painful effects.
aquablasters	mailing list for DSP programmers of ADSP-218x and blackfin. run by noah and inhabited by the syndicate and scores more! a good forum to ask questions.
music-dsp archive and mailing list	lots of wonderful information on DSP and musical applications. great mailing list too. the focus is algorithms, C programming, and PCs, but still inspriational for lower level DSP techniques.
audio programming on the ADSP-21056L	a tutorial on audio programming for the ADSP-21065L, another DSP manufactured by Analog Devices. the code is not compatible with the ADSP-218x, but similar enough that porting it is not difficult.
audio code examples for the ADSP-21056L	demo software from the audio programming tutorial listed above.
theoretical playground	new (as of 05/2004) discussion board covering all sorts of interesting topics relating to dsp and electronic music.
comprehensive audio/DSP index & info	an incredibly thorough listing of DSP subjects and information. maintained by julius smith from CCRMA.