I'm getting a little bored of my usual music, so who would you say are the best rock artists? I'd also like to get into Punk Rock, so maybe a few artists from that genre, too

errrh for punk rock , green day would be a good place to start.

personally i like

Nickelback
Rise Against
Lansdowne(kind of unkwown)
Linkin Park (old stuff)
Art Of dying

Nirvana.
Seether.

Linkin park?

I'd go for Bullet for my vallentine and System Of a Down ,just because of the rich pure lyrics.

It depends.Alternative rock or Heavy rock?
Just look around.

Here is small list of people I suggest you look into. I typically listen to all types of rock so there is a bit of a mix below.

Bob Seger, Supertramp, Wolfmother, Led Zeppelin, The Eagles, Foreigner, Pink Floyd, The Police, Flock of Seagulls , Golden Earing, Cheap trick, Thin Lizzy, Styx, Ted Nugent, Creedence Clearwater Revival, The Tragically Hip, Motley Crue, AC/DC ...

If you would like more names of people just let me know and I will tell you.

This might be helpful too - http://www.rock95.com/2011%20-%20Top500.pdf

Black Sabbath, Scorpions, Iron Maiden, etc. A majority of my interests have already been mentioned.

^this
Especially chester bennington

Nirvana (Scentless Apprentice, Blew, Beeswax)
Judas Priest (The Ripper, Victim of Changes, PAINKILLER)
Iron Maiden (Hallowed be thy name, Powerslave)
Black Sabbath (Children of the Grave, Into the Void, War Pigs)
Pixies (Gouge Away, Debaser)
Green Day (Android,, Who wrote Holden Caulfield)
Bad Brains (At The Movies, Banned in the D.C.)