There's a lot more Gn'R that you'd like if you like Welcome to The Jungle and Sweet Child O' Mine. As someone said, the best place to start with Gn'R is Appetite For Destruction. After that, check out both Use Your Illusion discs. Anything AC/DC is good. A lot of their stuff sounds the same to me, but I love it all so I don't care. Good places to start with AC/DC are Back In Black (the album and the song), Hells Bells, Highway To Hell, and You Shook Me All Night Long.
As for other stuff, one of my personal favorites that might fit your requirements is Lynyrd Skynyrd. I've only heard a couple of his songs, but you might also like Jonny Lang. Tom Petty might be another one to check out. Eric Clapton would be another good one. You might like Jeff Beck, also. They're not classic rock so much, but the style is similar, so you might like Steve Ray Vaughn and Kenny Wayne Shepherd. Some might laugh at this next suggestion, but you might also like Kid Rock's self-titled album that came out last year. He's gotten away from the rap-rock style of his previous work and moved more to the southern rock style. Sort of like Skynyrd but heavier. You might like ZZ Top, also.
I'm sure I could come up with more, but that's just looking through my Winamp playlist on my laptop. I've only got a quarter of my music on my laptop but that's probably a decent sampling and you'd probably like some of it.
Edit: Since there's a lot in there, PM me if you want specific titles or my recommendations. I'll boot up the desktop and tell you.