Unfortunately since the set is from 2007 there are only a few sketches on the RA site. I have been checking various artists postings on Scoundrel, deviantart, etc. I am pretty sure that I already have a sketch from this artist but I am not very good at comparing artwork.
PC Jake Fisher - If I don't have it, I want it!
Looking for Doctor Who Battles in Time, Doctor Who autographed index cards and Solomon Grundy