1] Johnson and Rees "Numerical Analysis" Addison Wesley
Undergrad. level broad intro.

2] Numerical Recipes in X (X=c,fortran,pascal,etc) Tueklosky and Press

3] Young and Gregory "A survey of Numerical Mathmematics" Dover 2 volumes.
Excellent overview at grad. level. Emphasis toward solution
of elliptic PDE's, but good description of methods to get there
including linear algebra, Matrix techniques, ODE solving methods,
and interpolation theory. Biggest strength is it provides a coherent
framework and structure to attach most commonly used num. methods.
This helps understanding about why to use one method or another. 
2 volumes.

4]Hockney and Eastwood "Computer Simulation Using Particles" Adam Hilger
Good exposition of particle-in-cell (PIC) method and extensions.
Applications to plasmas, astronmy, and solid state are discussed.
Emphasis is on description of algortihms. Some results shown.

5] Birdsall and Langdon "Plasma Physics via Computer Simulations" 
PIC simulation applied to plasmas. Source codes shown. First part
is almost a tutorial on how to do PIC. Second part is like a
series of review articles on different PIC methods.

6] Tajima "Computational Plasma Physics: With Applications to Fusion and 
Astrophysics" Addison Wesley Frontiers in physics Series.
Algorthims described. Emphasis on physics that can be simulated.
Applications limited to plasmas, but subjest areas very broad,
fusion, cosmology, solar astrophysics, magnetospheric physics,
plasma turbulence, general astrophysics.

Some parts © 2009 Advameg, Inc.