Wow, there are some sweet dream books listed. Mine kinda pales to some, but hey
1 - Strange Tales 110
2 - Showcase 23
3 - Showcase 24 (owned it once, sold it, WHAT was I thinking...)
4 - Green Lantern 1
5 - Amazing Spider-Man 14
Strange Tales 110 annoys me because, barring Spider-Man (and I really have no interest in a AF 15) Doc is the one that shows up most in my collection without me owning his first appearance.
Ya, I know they are available all over the place, I just haven't been able to afford one that I would actually want to own yet