They're available from all sorts of industrial outlets but I have always found RS by far and away the best and the cheapest.
http://uk.rs-online.com/web/
You don't HAVE to use LISTA cabinets, the two are unconnected, but together they can make for a fantastic amount of storage in a very condensed volume.
What I like most is that every time you open a drawer you are reminded of what you've got and not got, and as your memory goes this is no bad thing.
I have been using these for over 20 years now, having initially used them in a professional workshop and parts context, during which time the design has remained unaltered, so my systems have been able to grow and adapt without ever having to change horses mid-way.
I only use four different sizes, and find they cover 100% of my requirements - although the RAACO range is much bigger and includes cases where the interiors are composed of permutations of the same layouts.
I've never found a solvant that fazed them, even if was never my intention to involve them in all sorts of deviant behaviour for which they were not designed, nor even broken or cracked the plastic.
I think they're fantastic value for money, especially the three smaller sizes, and I've never conciously thrown one away or worn it out.
The geometry of them makes it easy to commutate and reconfigure in a second your layout when you add a new reference, or change the amount you're storing. They're all 47mm high, and the bigger sizes are just multiples of the smallest 39mm x 55mm unit, hence the ease of composition and layout.
They also make good little containers to group bits by function and location when stripping cars/bikes/machines.
So FWIIW here are the RS (ex Components) references.
(Shame that PhotoBucket's picture editor can't manage to get pictures the right way up, whichever of its clunky features I waste my time trying to use - maybe we should ask RAACO to set one up.)
Tiny - A9-1 - 47mm x 39mm x 55mm RS reference 655-4519 - 8.13€ + VAT for 16 buckets
Small - A8-1 - 47mm x 55mm x 79mm RS reference 655.4654 - 9.84€ +VAT for 16 buckets
Medium - A7-1 - 47mm x 79mm x 109mm RS reference 567.095 - 1.05€ + VAT each
Large - A6-1 - 47mm x 109mm x 157mm RS reference 655.6739 - 4.55€ + VAT each