Osprey Publications is having one of their really nice sales. All kinds of reference books that cover periods and troops that WGA makes are on sale.
A lot of Osprey game rules books as well.
Obviously it's bad form to post links to competitors on the WGA forum. But Osprey publications isn't a competitor. Their books compliment WGA miniatures and will inspire you to get more.
I ordered last week and got my first shipment in today. The French Soldier VS German Soldier is really good so far. I challenge you to read this and not pick up a box of WGA French ;)