Al posted a link to a book in this collection in a recent thread, so I thought I'd mention it here in the "references" section of the forum and provide a link to the collection as a whole.
At this web address you will find a link to the University's collection of World War I books online (102 volumes). Just below this link there is a list of journals covering the war. There are many photos of tanks, carts, motorcycles, artillery pieces, trench railways, and etc. Don't miss the excellant WWI photos in these books and journals, and be sure to tell us all about your "discoveries"!