The Roll of the House of Lacy : Pedigrees, Military Memoirs and Synoptical History of the Ancient and Illustrious Family of De Lacy, by De Lacy-Bellengari
This book is at Ancestry's website, here:
http://search.ancestry.com/search/db.aspx?dbid=13578I wish I'd known before I bought a copy!
I'll be adding this to the links on Board Information, if it lets me.