Can anyone recommend a site or source that has good backing tracks with guitar? I find myself playing with guitarists a lot- I jam with a guitar duo doing a friendly garage thing and am also in a band that covers rock and country that actively does gigs. I feel I need to get better at recognizing the key these guys are playing in and thought I could improve if I practiced more with recorded guitar. I am struggling with recognizing the "auxiliary" notes I can play beyond root and how to expand beyond unison with the strings- second guessing myself when I try to venture out in my fills or solos. Maybe some other advice on how to get better there...