For an unusual liastening experience, try Brave Combo. They were a polka band. They are a polka band. But they play the twist, jimi hendrix, hava na gelah (sp?) etc. on their electric guitars and accordians. It has to be heard to be believed. I doubt if mudcatters would be disappointed.
If there are any good Spanish language radio stations where you live, and if they cater to the local Mexican population, the popular Mexican music is filled with polkas.
I've been noodling around with a few polkas on fingerstyle guitar for years, trying to get something down.
And, I believe Duke Ellington was credited with the "teo kinds of music" quote, although that may be as much modern folklore as actual quote. Like all good folklore, the truth of its meaning carries it irregardless of accurate details.