Apologies to everyone - it appears I forgot to draw the sketch challenge back in April (I just found the prize in my box when I went to send out the latest one...oh dear...).
I'm really sorry for the oversight. The random choice of winner is DEBS, who created a lovely card which you can see here: http://debs-eternity-cards.blogspot.com/2009/03/craft-stamper-challenge.html
Please get in touch and I will send your prize (some lovely Papermania stamps) out to you asap.
Sorry again folks - I'm only human!