This page has some good advice on and descriptions of ways to attach gear on the outside of your backpack. Sectionhiker.com
This guy has, crudely in some respects, patched together an interesting series of pages and links on the historical roots of most backcountry gear and gear companies today. A lot of this information is not easily found even with today’s wide-reaching search algorithms.
From the origins of companies like Sierra Designs, legendary Berkeley-based Ski Hut, little-known Oregon outfits…if you have any interest at all in how what you carry on your back came to be you’ll be engrossed in these pages.
ZPacks accessories sell some pretty nifty lightweight gear for hiking and backpacking.