A good introductory material on Matlab is Chapter 1 in Cleve Moler's book, "Numerical Computing with MATLAB". This chapter is available online at http://www.mathworks.com/moler/intro.pdf
An exerpt from a Matlab Companion for Multivariable Calculus by Jeffery Cooper, is available online on Jeffery Cooper's webpage at
http://www-users.math.umd.edu/~jec/matlabintro.pdf
There are many books. Check: A guide to Matlab: for Beginners and Experienced Users by Hunt Lipsman, and Rosenberg