My first was a Ral Partha Paladin (posted as a pic, in some thread or another), which I bought already painted, and painted over that (without stripping it) when I was twelve, in Testors Enamels.
After that, I got Ral Partha\'s dwarf box set and halfling box set, because the hobby shop in the neighbourhood was selling them really cheap, together.
Funnily enough, 20 years later, I won an auction on Ebay for a lot of about 120 minis, and those same halflings and dwarves, complete with my own original paint jobs (rather chipped but definitely my work), were a part of that lot.
God only knows how many times they changed hands between me and coming back to me again.