For now, this list mainly concerns comic book adaptations, but I love Howard's stories too, so that may change in time.
The Conan Chronologies
Comics for Education & Self-Improvement
Rare Conan Coins: Part 1
Roy Thomas on Conan and Dogs
Rare Conan Coins: Part 2
My sole entry on King Kull (for now)
Robert E. Howard's King Kull in Comics
Three Posts on Red Sonja
Red Sonja and the Unicorn
Red Sonja Touches People's Lives
Enjoy your Hyborian adventures!