http://stefanssketchblog.blogspot.com/ is the source, and you can page through and look through all the rest of the art Stefan has posted... awesome!
or check the Flikr page http://www.flickr.com/photos/stefanmarjoram/6520015323/in/photostream because you'll enjoy the series, which gets released one image a day, and they are for sale too!
"Throughout December Ill be adding a new one every day. Original pencil and watercolour on 6x4inch (postcard size) watercolour paper . £24 inc shipping worldwide" www.etsy.com/shop/StefanMarjoram