I recently bought a new Wacom Bamboo for €50. It has been great for me as I am a photographer who has always been into drawing and painting. This tablet makes me want to experiment all the time and that is why it has been a good investment.

It comes bundled with a great painting program called Artrage and this is one application that is a great example of good human computer interaction.
It feels like real painting but it is waaaay more fun.

Its only 50 quid mate so just buy one and have fun.
You can always buy a €300 super duper version later but I dont believe that tools make the workman.

Have fun.