It seems that "Trigun" will be released in 2 giant books by Darkhorse (The second may have already been released aswell, but i havnt picked it up)
"Trigun Maximum" will be released in 4 volumes by Darkhorse aswell.
As far as i know, u will just have to wait and get the english releases to see if it goes any farther in depth then the anime did. I'm already aware of one or 2 Drastic changes that they made in releasing the anime.
Either way, the manga is a good read. I picked the first one up at a local Barns and Nobel. GL!
