This has to be the best ukulele chord book ever. I find that even after over 15 years playing my ukulele, I keep it close at hand - you never know when you have to find a better way to grab that chord that's giving you a bit of trouble.
I found it at my local acoustic music shop, Dusty Strings, for $15.
The down side is that they only made this book for GCEA tuning, so you baritone users have to transpose a little to make it work for you. I use a bit of white tape to cover up the printed chord callouts in the book... and write in my bari chords above the proper fingering.