If you've never used one before, a tablet will revolutionise your Photoshop/2D/postwork. Here in the UK, I can only afford a cheap one - Aiptek.  Watch out for Aiptek though - the tablet works fine, but the pen monitoring software (ATWUSB.EXE) seriously conflicts with Poser and causes Poser to crash each time I try to load it.  If I disable ATWUSB.EXE before launching Poser it's ok, but it's a pain and then needs to be relaunched when you want to use the tablet.  I've given up producing any artwork now, but if I ever start again, I consider a tablet to be a must for postwork. 

Hi there I'm living too in UK and I would have a look at PC World offers,they have now for £39.99 Wacom Bamboo or for £59.99 Wacom Intuos (CTL-480S-ENES),I was looking on Bamboo,which is right now cheapest at PC World 

Hope this helps

Thanks,Jura