WW1 Arty is a kind of confusing subject. At least to me. At least when compared to WW1 Armour, where the types are few and easily recognizable. But guns: there must be many, many hundreds of them.
What are the best books to get? And I mean *books in print*, not rare, out-of-print ones, costing hundreds of $$$$$ What are you recommendations?
I agree on that bit about WW1 Artillery being a big and confusing subject. I'm myself is only slowly getting grips on it.
If you need some good general reference material, I would recommend
1. Franz Kosar: "Artillerie im 20. Jahrhundert". Simply a small encyclopedia, with each gun getting one pic and one page of tabulated prestanda. You will find it ALL here. Including WW2 and modern.
2. Ian Hogg: "Twentieth-Century Artillery". The same idea as Kosar, but colour artwork, and not as comprehensive: only 300 guns are covered here, but the most important ones, and from the whole century.
Both are in print and pretty cheap. You will find them om Amazon, Kosars book on their German subsidiary: .de.
German Artillery Of World War One by Herbert Jager
You can find both on Amazon.com as either new or used. New is usually between $20-25$ used a little cheaper. Both contain detailed pics and diagrams on many different types of guns And shells. Well worth the price. I hope this helps.
The guy has a huge collection of different weapons and other WWI items in the Objects that Tell section but his section on WWI artillery especially the ammunition and fuzes area contain excellent diagrams and descriptions that I havent seen in any books on the subject. He also has a great section on different grenades and has recommended books in each area. Definately should check in out. He is also very nice and helpful emailed him a couple questions and he responded the next day.