I'm looking for background of the Corporate Sector that extends past the wiki. Two DC novels brought the CSA back into Canon but it's still not good. So I was wondering where to look first.

Wookieepedia lists the following books are sources for the Corp Sector, but I expect it to be slim pickings...

Lords of Nal Hutta

Strongholds of Resistance

Fly Casual

It also lists all the previous RPG books its mentioned in, or contain information (under the legends tab, at the bottom, under Sources)

Edge of the Empire Core Rulebook p. 352 - 353. Just enough info to wing it.

And it's super cheap on Amazon, too. 12 bucks for everything you'll need (other than stats)!

That book is available on the d6 Holocron, I believe...

That book is available on the d6 Holocron, I believe...

Yup. See http://www.d6holocron.com/downloads/books/WEG40042.pdf

Many thanks

HSatCS is great for info on the governance of the Corporate Sector and some cool NPCs but provides little to no planetary data.

There is a little bit of information about the Corporate Sector and it's worlds in the Essential Atlas, including a planetary profile on Bonadan,