There's not too much work on the Imjin War in English. Here's some books you might want to check out:
The Imjin War: Japan's Sixteenth Century Invasion of Korea and Attempt to Conquer China by Samuel Hawley - Sill haven't read this one but it has gotten rave reviews from people I know and respect as scholars. It is pretty pricey though.
Samurai Invasion: Japan's Korean War, 1592-1598 by Stephen Turnbull - This is one of Turnbull's better efforts. It still leaves a lot to be desired, but it's a good buy.
The Samurai Invasion of Korea 1592-1598 by Stephen Turnbull -The shorter Osprey version of the above title. Probably your best bet for a starting resource.
A Dragon's Head and a Serpent's Tail: Ming China and the First Great East Asian War, 1592-1598 by Kenneth Swope - This book has been roundly crticized by a ton of people I know so I have stayed away from it. However, if you want info on the Chinese side of things, you may want to pick this one up.
Of course, you can always PM Historum member Rollingwave. That would save you some $$$.
If anything though, it was the least significant from China's perspective. they lumped it in with two other quasi war, one was a military garrison rebellion and the other was a indeginous tribe rebellion. not exactly earth shattering stuff.