Depends which bands you know. I am not a prog guru, but I would say Yes, Genesis, ELP and King Crimson should be a good starting point. Dream Theater are also a great band, although more on the metal side.
King Crimson, Rush, Mars Volta, Yes, Radiohead(I'd consider them prog) are my favorites, but we do have a whole forum on Prog.
Oct. 20th, 2009: New guitar AND front row for Mars Volta.

Quote by denizenz
Is that a ukulele in your pants, or did you just rip ass to the tune of "Aloha Oi"?

I met Sonic Youth on June 30th, and Mars Volta on Oct 20th.
Ark (the original 80s not the new one) a few sites and youtubes exist of them. They were Prog-punk and personal mates
It Bites
The Nice
Barclay James Harvest
Who was that other, quite good lot? Oh yeah, Pink Floyd
I pick up my guitar and play
Just like Yesterday

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