Hey man! So glad you are digging the lessons! I would love to teach more Lizzy, but there is an extensive approval process before we can teach certain songs. Be sure to click on the following link and post your requests:

http://www.guitartricks.com/forum/forumdisplay.php?f=58

As far as your amp question: I try to break down every song to the 3 general categories of amps: Marshall style, Vox AC30 style, and Fender style. Each of the 3 have a very distinct voicing for which pretty much all other amplifiers are based on. In the case of Thin Lizzy, or any classic hard rock from the 70s, 99% of the time it's going to be a Marshall Plexi amp.

For Guitartricks lessons, I use my Pod XT for everything. On my Xtone Les Paul style guitar, the pickups are stock Seymour Duncans.

Thx for the great questions and requests!
Keep rockin'!!
Mike