Hi all,
Yet another good book on DSP is Sanjit. K. Mitra (TMH) a quite comprehensive and athouritative, which includes heaps and heaps of MATLAB® codes. More so those codes can be downloaded for free. I do not have the link with me right now, whereas, a google run can be benificial..!! The best way to learn any tool (and more so in case of MATLAB®) is to use it. If one is familier with C it becomes still more easier....!! student version of the tool is free for download from it's official site - MathWorks™
All the best,
Sai