I just saw that I mentioned this book in one of my first entrys, but forgot to give it the credit it deserves. I think this is a real worthy publication. Lots of tunes included. Every tune is written down in notation and tab. You can find the melody lines plus backup for every tune. On the enclosed CD every tune is played with melody on one channel and backup on the other channel, so you can listen only to the line you want to practise. Very useful.
Most of the tunes are traditional Irish tunes. There are some original tunes from John and some american tunes and even 2 Jazz tunes to be found, too.
More infos on John's website:
Here you can listen to a sample from the CD: man of ulster
Here's a video by his band "The Wayfaring Strangers"