In this page you can download the implementation of the bandwidth minimization
algorithms described in the paper:
G. Del Corso and G. Manzini
Finding Exact Solutions to the Bandwidth Minimization Problem
Computing. Vol. 62, (1999), 189-203.
The source code is available under GNU GPL. Unfortunately there is very little documentation so I highly recommend reading the paper before trying to use this program. Contact me if you need assistance.
(Update: May, 2005) The results of this paper have been recently improved. I strongly suggest to read the paper Laying Out Sparse Graphs with Provably Minimum Bandwidth by Alberto Caprara and Juan-José Salazar-González, INFORMS Journal on Computing, Vol 17, n. 3. (End Update)