John Lewis

The "Never Knowingly Undersold" department store features sewing machines, materials, and other supplies of use to the average fursuiter. The Oxford Street shop also features gorgeous, but ridiculously expensive, luxury faux-fur.

The McCalls (and probably others) animal suit patterns that appear in the FAQ can be ordered here. Plastic mesh can be found in the cross stitch section.

Unfortunately the online store does not offer these kinds of goodies at the time of writing. You can find the location of the real stores though. Note that not all John Lewis stores open every day of the working week. The Milton Keynes store for example is close Mondays (and very irritating it is too).