Listmania!
Excellent Columbia river gorge guidebooks
By an Amazon.com customer
Afoot & Afield Portland/Vancouver: A Comprehensive Hiking GuideAfoot & Afield Portland/Vancouver: A Comprehensive Hiking Guide by Doug Lorain
Buy new: $15.56 / Used from: $13.19
Haven't got this one, but i hear its OK.
Curious Gorge (50 places to discover in the Columbia River Gorge and Hood River)Curious Gorge (50 places to discover in the Columbia River Gorge and Hood River) by Scott Cook
Buy used from: $18.94
Lots of pictures, cool stuff that the other guidebooks don't usually cover such as migrating salmon, ice caves, and dams on both Hood river and White salmon River.
60 Hikes within 60 Miles: Portland, 3rd: including the Coast, Mount Hood, St. Helens, and the Santiam River (60 Hikes - Menasha Ridge)60 Hikes within 60 Miles: Portland, 3rd: including the Coast, Mount Hood, St. Helens, and the Santiam River (60 Hikes - Menasha Ridge) by Paul Gerald
Buy new: $11.53 / Used from: $8.99
Long descriptions, but not as many pictures.
100 Hikes in Northwest Oregon & Southwest Washington, 3rd Edition100 Hikes in Northwest Oregon & Southwest Washington, 3rd Edition by William L. Sullivan
Buy new: $11.53 / Used from: $10.70
Sometimes considered "the bible", but aimed towards total hard-case hikers.
Pokin' Round the Gorge (A Sexy-Romantic Guide for Columbia River Gorge Lovers)Pokin' Round the Gorge (A Sexy-Romantic Guide for Columbia River Gorge Lovers) by Scott Cook
This one is the most fun, and the only one in color. Note though, it says "r-rated" for good cause! I love it!