They are called Play-Along Tracks and you can access them in the left sidebar.
Here’s the direct link: https://www.realguitarsuccess.com/play-along-tracks/
Sometimes I call them Jam Tracks… I haven’t decided which I like best 🙂
This is where I’ve compiled the different backing tracks.
You’ll find that courses (like Improvisation FastTrack) have tracks included right there on the course page and lesson page.
BTW… I’ll be talking about Improvisation at tomorrow’s (Thursday 11/2/17) RGS Live.