If you're interested in helping out the Archive Coalition, then you will need to speak with Master Archivist Augusta Brown in Embry Crossroads at X:4240944, Y:3223030. She will give you the knowledge used to combine books into Sets, Collections, and the Omnibus. It's that simple really, now you'll just need to build up your book collection and start making the Omnibus.
The books used for the Omnibus are found in scavenging nodes called Curious Debris and Sturdy Bookshelf. The bookshelves are only inside buildings and are very rare in the plateau. The debris is the best way to go for fast gathering of books with over 150 documented waypoints on file. Curious Debris also comes in 3 forms: bags, barrels, and desks. Each of these contains a specific drop log of 6 books, they do not mix and match, it is always the same 6 books for each node plus Scrap Paper once in awhile. The bags and barrels types are most common and respawn within a few minutes making these the easiest to collect. The Desk nodes however can take as long as 30 minutes to respawn and thus the 6 books only found within these are the rarer types, especially the Eat Me: A Cannibal's Manifesto book.
Now that we know where to find these books, let's briefly explain what to do with them. For starters, there are 18 books in total scattered throughout the central and upper plateau regions. These books combine into 9 Sets, one for each tradeskill minus construction. The sets are then used to create 3 Collections, each containing 3 Sets in one. These Collections pertain each to Combat, Research, and Support. Once all three are acquired, then you can combine them into the Omnibus.
When all is said and done, you will want to return to the Archive Coalition and speak with the various mission givers to receive your rewards. The Collections each net 1AP and the Omnibus gets 5AP. These are the main reasons most people collect the books and this makes the Omnibus highly sought after. That's the jist of it, now it's time to get a bit more detailed.