Where in the UK can I get a small heater for my garden shed to keep
away the damp?

I store some personal possessions there like clothes, books and so
on. This means I don't want a heater which makes a smell - like
paraffin.

The shed is small (about 2m x 2m) so I don't need a powerful heater.
There isn't enough room for a heating panel as big as this:
http://snipurl.com/n76l