I just saw today that there are 4 titles from James Durham on the Community Pricing at Logos. The titles in the collection are (greatly abbreviated): Practical Exposition of the 10 Commandments, Unsearchable Riches of Christ, An Exposition of the Whole Book of Job, & Treatise Concerning Scandal–all for the minimum bid of $18. However, I would HIGHLY suggest you get printed copies of what may be available from Chris Coldwell at Naphtali Press. He makes some really high quality books. The Logos files would be a good tool to use for searching. You just can't beat a physical book for reading.