Hello RachT, I'll attach a pdf that has very simplified diagrams on the desirable form to which a young almond tree should be pruned for nut production. However let me make a few points as well hopefully they will both make sense and be useful to you and others.
Whenever we are asked to prune trees for any client we make sure that they (the client) understand what is to be cut and why, what the predicted outcome of the cuting will be, and if we are limited in the dose applicable to the tree (the amount of live tissue removed) why that is and how soon we would need to return to complete the works.
Old and storm damaged trees are tricky and sensitive to prune. The older a tree becomes the less live tissue you can remove before adversely impacting the long term health of the tree. Its very hard to tell from your photo just what the form of the tree is really like, its impossible (of course) to tell what was removed and why. It would be dissapointing if you can't get the Arborist to return briefly and reinspect the tree to give you a quick verbal on its current health and future prescritions for any works (of which additional pruning may well
not be one)
The best book on pruning I have is Edward F Gilman's An Illustrated Guide to Pruning ISBN 0-7668-2271-0 published by Delmar Thompson Learning.
However as I've tried to indicate there is a lot more to pruning trees than knowing where and how to cut...dose is the key principal and I'm afraid there is no single book that can deliver that knowledge and understanding, it differs for every tree species/age/vigor/vitality/environment/season etc.....
So please try to get in touch with the Arborist you used, if they are no help go here
http://www.treeguild.com/contractors.shtml and find a qualified contractor who will come out and help you.
http.pdf_almonds-garden-h3136.pdf FS2006_FRUITPRUNING_MSIVYER.pdf