found a few sites recently, by accident, which may be of use to some (especially those down-underish):
Driwear Incontinance Products | Plastic Pants | Rubber Pants | Incontinence | Adult Diapers
that's a N.American site, but they ship abroad.
Australia and New Zealand
Victoria Healthcare Melbourne | Disposable Incontinence Products
i've not tried any of them, but, if you have, please comment, for the benefit of others (personally, i'm interested in the Driwear products, if shipping and customs aren't a problem).