- The Journal of Combinatorial Designs has some information including its contents back to volume 1.
- The Handbook of Combinatorial Designs has a website that lists new results in design theory that have been discovered since publication of this excellent volume.
- Designs, Codes and Cryptography has a site with its table of contents.
- At http://mathworld.wolfram.com/topics/Designs.html, you can find definitions and a short discussion of many of the important concepts and objects on design theory.
- At http://www.utu.fi/~honkala/designs.ps, Ian Anderson and Iiro Honkala have placed notes for a "Short Course in Combinatorial Designs (about 40 pages, 272K, in postscript).
- I found lots of good design theory links (including a link to this page) at the Design Theory Page at Queen Mary College.
- DesignTheory.org is funded by the UK government provide various resources for Design Theory through the Internet.
- The Designs Archive at Statlib has some very useful programs for making orthogonal arrays
- The Infography about Symmetric Designs in Combinatorics
- Neil Sloane at AT&T has a big collection of examples for orthogonal arrays and also for Hadamard matrices. He also maintains a web page for GOSSET: A general purpose program for designing experiments.
- The Guide To Available Mathematical Software at the National Institute of Science and Technology is a cross-index and virtual repository of mathematical and statistical software components of use in computational science and engineering.
- DISCRETA is a great program for finding t-designs.
- The La Jolla Covering Repository contains coverings C(v,k,t) with v<=32, k<=16, t<=8, and less than 5,000 blocks.
- The Netlib Repository contains a collection of mathematical software, papers, and databases.
- Gordon Royle's combinatorial catalogues contain lists of designs, graphs, etc.
- Listings of small latin squares can be found on Brenden McKay's Latin squares page.
- The Annals of Combinatorics (Springer) is building up a web site: http://www.combinatorics.net which is called the Combinatorics Net, this site is also intended to serve the general combinatorics community.
- The Open Directory Project links to design theory pages.
- A general list of math sites (listing the Handbook :) can be found at
Math Resources -
directory of Math related websites.

- Kishore Sinha's web site contains updated group divisible designs and partially balanced design tables from Clatworthy(1973). In addition there is a nice bibliography.
- A listing of association schemes on a small number of vertices as well as other information on association schemes can be found at http://kissme.shinshu-u.ac.jp/as/ .