I think you're wrong. Good rock is where you find it. Nowadays it's much less popular than it once was, but there are plenty of good bands out there. Others have pointed you to Mastodon etc., so I won't bother. All these bands have had at least one new release in the past year or so.
High on Fire - Matt Pike's band. Very heavy, and very good.
Abdullah - Cleveland based Sabbathy band.
Place of Skulls - Victor Griffin's (of Death Row and Pentagram) band. Just released their third album.
Alabama Thunderpussy - Great oldschool styled rock band.
Cathedral - They're still making excellent stuff. Saw them tour for their latest release last year, and loved it. Some of my friends were the supporting act too.
The Hidden Hand - Scott Weinrich's project. Very atmospheric, cool and downright brilliant music. They released an EP+liveDVD on limited release a few weeks ago, and it's brilliant.
Clutch - Their release (Robot Hive/Exodus) last year was another excellent one.
Spiritual Beggars - Michael Amott's hard rock band. Love their stuff.
I don't listen to a huge amount of the following stuff, but it's great stuff when I'm in the mood:
Amon Amarth - great Viking metal out of Sweden. Bonecrunching riffs, and they actually write really good lyrics.
Arch Enemy - Swedish death metal from Michael Amott. Amazingly good riffs and solos.
I don't think that rock is dead at all, but if you want to listen to good rock it definitely takes effort. I've probably forgotten some of my favourite (and current) bands in the list as well.