In reply to Paul Evans: Ooo goody
My four would be
Deep Play - P Pritchard; 1st Edition signed by both Paul and Mr Yates - dedication by Paul is very personal to me.
Portrait of a Mountaineer - D Whillans; 1st Edition signed by Don & Mr Bonington - Don is a big hero of mine and to have a book signed by him is special to me.
Eiger Direct - Gillman & Haston; 1st Edition signed by Bonington. A very underated book about a great story fully of hero's, villans and daring do.
Total Alpinism - Desmaison; 1st Edition. Great book about the man who was the father of winter Alpinism and spent most of his time in and out of trouble (mainly in).
All four books have had special meaning to me at some point in my climbing life and remain so.