My favourite resources on the web.
The Art of Counting with Beads
Site contains history, instructions and a Java abacus.
The Abacus - Beads, Rods and Frames
A good collection of software, including dictation software that reads sums to you to help you practice.
Abacus - Wikipedia page
Where would we be without wikipedia? In the dark, that's where.
Abacus: Mystery of the Bead
Totton Heffelfinger and Gary Flom’s site, a nice collection of techniques, info and history
Gareth Griffiths’s site, the Welsh soroban resource, including teaching aids and information on the benefits of soroban use for the dyscalculic
If you're interested in purchasing a soroban, I sell
them in my shop: