For an introductory book on numerical methods, see
Numerical Mathmatics and Computing, 7th Edition ,
by David Kincaid and Ward Cheney, Brooks/Cole: Cengage Learning, 2013

For a more advanced book on numerical analysis, see
Numerical Analysis: Mathematics of Scientific Computing, 3rd Edition ,
by David Kincaid and Ward Cheney, Brooks/Cole Publishing, 2002

For an elementary book on linear algebra, see
Linear Algebra: Theory and Applications, 2nd edition ,
by David Kincaid and Ward Cheney, Jone and Barlett Learning, 2012

For software packages, see
NSPCG
ITPACK