Was trying to find a PDF editor and basically found these two: PDFedit and pdftk. There were recommended in this thread, as well as this one, on Ubuntu Forums. I installed PDFedit using this command:

sudo apt-get install pdfedit

And this should install pdftk:

sudo apt-get install pdftk

Just note that pdftk has no gui, but I think you can download one here. not sure how well it’ll work, but as far as I can tell, that’s about the only gui for it…