My first recordings purchased were 45s...
The first recordings I ever paid for (my allowance) were 45s. No idea what was first but the early 45s were Timothy by The Buoys, Guitar Man by Bread (yeah, sorry), Alright Now by Free, Sweet Home Alabama by LS... and some others.
I think the first vinyl LP I ever bought was Vices/Habits by the Doobie Bros.
But (check this out) my first LP ever (that I got for Christmas from my parents in '68-69-ish) was 'Mr. Spock's Music From Outer Space' by Leonard Nimoy. I ROCK!
I was also given a 2-disk cutout record of Woodstock 2 - Hendrix, CSNY, Airplane, Havens... probably changed my life musically even more than Mr. Spock.
-=sf=-