I've got Lecture Notes - It's small and very readable, and so far has been in enough detail. Surgery is very much 'post grad' so you only need an understanding of the basics (Well that's how I've interpreted it) and management prinicples etc.
Principles and Practice good because it has a big chunk on management of a surgical patient which is what you will need as a HO, although detail on the surgical procedures and conditions is there too.