Computational Complexity - (Birkhäuser) Tables of contents from vol.7 (1998) on. Full text to subscribers via LINK. - http://www.springerlink.com/content/1420-8954/
Complexity and Approximation - Combinatorial optimization problems and their approximability properties: by G. Ausiello, P. Crescenzi, G. Gambosi, V. Kann, A. Marchetti-Spaccamela, M. Protasi (Springer, 1999). Table of contents, errata, software supplement and a continuously updated - http://www.nada.kth.se/~viggo/approxbook/