The First LP I ever purchased was Iron Maiden - Piece of Mind.

I shortly afterwards underwent a change of musical tastes, which brought me to my first cassette, which was either The Cure - The Head on the Door or Devo - Oh No! It's Devo!

My first CD ever was actually a quadruple purchase. I got 4 Depeche Mode CDs: Strangelove Single, Black Celebration, Music for the Masses, and Some Great Reward.

Never bought a LP
First cassette: Cocktail soundtrack. I bought that just for the song Kokomo
First CD: Michael Jackson's HIStory

vinyl...."Meet the Beatles" (I'm not called Gramps for nothing!)

cassette....lost in the fog of the 70's?

CD.....was waiting for the digital tape revolution,??? Pink Floyd "Dark Side of the Moon"?

Hmmm, this is tough. My memory sucks...

First LP: I never bought one myself, unless you include winning a Kansas record at a town fair. (don't remember which)
First cassette: It's a toss-up between Men-at-Work's "Business As Usual" or Styx's "Kilroy Was Here"
First CD: I honestly don't remember. It was a bunch from the Columbia Music Club.