MOST Supernova Remnant Catalogue
SNR catalogs and images from the University of Sydney.
http://www.physics.usyd.edu.au/astrop/wg96cat/

List of Supernovae
Provides details on all supernovae reported since 1885, as well as four earlier galactic supernovae.
http://cfa-www.harvard.edu/cfa/ps/lists/Supernovae.html

Bright Supernovae
Contains a list of the currently observable supernovae, along with information on their location and reference images.
http://www.ggw.org/asras/snimages/

SAI Supernova Catalog
Sternberg Astronomical Institute - Moscow, Russia.
http://www.sai.msu.su/cgi-bin/wdb-p95/sn/sncat/form

Supernova Remnants (SNRs) Directory
An index to SNR database including radio maps, optical and X-ray images.
http://cats.sao.ru/~satr/SNR/snr_map.html

AstroArts Novae and Supernovae
Observable Novae, and Supernovae. Plus a database of all current novae, and supernovae. Includes finding charts for bright objects.
http://www.astroarts.com/