There is an English publication of Anarcho-Syndicalism in the 20th century by Vadim Damier. http://www.revolutionbythebook.akpress.org/anarcho-syndicalism-in-the-20th-century%E2%80%94a-new-book-from-black-cat-press/
It is a very good publication for people first interested in the topic. Vadim's 2 volume history of the IWA is very good, but I am afraid that won't be out in English for some time. (Thick book.)
I found this book rather good for basic information, so I recommend people who have organizational libraries pick it up.
We found it worthwile to translate into Polish - hopefully out in January.