James Warren ran a rather unique publishing company. He didn’t pay top dollar for top talent, and instead offered creative freedom that attracted some of the best artists working at the time to draw stories in Creepy, Eerie, Blazing Combat and, later, Vampirella. The contributors included Frank Frazetta, who was painting covers for Warren during the period he was also creating his famous Conan the Barbarian covers for Lancer.
Somebody must think that the Warren catalog is in the public domain, because there’s a scanned archive of many Warren magazines available at this link on Archive.org.
Issue #7 includes this concise Frazetta biography. I replaced the fan art on the page with the cover of Creepy #4.