Waaaay back in 2002, all 8 pages of original art for the very first Swamp Thing story sold at auction. Now, this is not the exact same character you might be familiar with but sort of a proto-Swamp Thing. As you read the story you may notice the character's name is Alex Holland, not Alec Holland. In fact this version of Swamp Thing was retconned into the Alan Moore version of Swampy as one of the earlier plant elementals.
Frankly I never found Swamp Thing as interesting as in those early Berni Wrightson and Len Wein days (no offense to Alan Moore but he turned the character into something else entirely). After Alan Moore the horror aspect was diminished (at least in my mind) and I lost interest. Swamp Thing always worked best as a horror-themed character and was never written or illustrated better than the duo of Len Wein and Berni Wrightson. Do yourself a favor on these pages and actually look at the artwork: it is absolutely phenomenal. It's difficult to sometimes see the actual art with the color but this is a story I believe works almost better without it. Very, very moody and atmospheric.
Anyway, long-winded introduction aside, these are the actual 8 pages of original artwork for the story, culled from the Heritage Auctions website.
So, from House of Secrets #92, here is...Swamp Thing!