Very good news: Today Logos Bible Software put their 30-volume C. S. Lewis Collection on pre-pub.
Recommendation: Pre-order it now. (1) You’ll lock in a better price, and (2) it will help the collection release sooner.
Update (3/23/2015): I’ve added this new collection to my Logos library, and I just added each book one by one to my Zotero library. Love it.
Even if you already own some or all of these volumes in print or another format, you should seriously consider getting them for Logos. Its powerful search engine, specialized resource tagging, multi-platform apps and syncing, integration into an interconnected digital library, and notes and highlighting tools add significant value to the content.