The first 'heavy metal' single I bought was "I'm The Man" by Anthrax. I heard it on the radio and thought it was quite funny, as the end of each line didn't rhyme although it was obviously supposed to.
I bought it from Tesco in Walkden when I was about 10, I think, and I remember the woman behind the counter giving me a funny look when I bought it.
It turned out that the radio version was far far cleaner than the uncensored vinyl version. I was mortified when I got home and played it to my parents.
Anthrax were OK when Joey Beladonna was in it, but I still prefer John Bush as the singer.