I don't know what Justin is using. What are you missing in SongBook and OpenSong?
My personal approach would be using specialized software like MuseScore or Guitar Pro for creating the musical notation and then include those within some sort of desktop publishing/word processor software (e.G. Apple Pages being the simplest, otherwise Adobe InDesign, Scribus or LaTex) to create an actual book with page layouts to my taste and requirements, free text and so on.
Don't know if there are good options that combine the two types of content well in one software.
If its just about writing down lyrics with chord names on top, I think every text writing program will get the job done.
So far the things I'm working on are so simple that i prefer writing it down by hand in my music notebook having blank pages on the left and staff lines on the right. I also remember everything much better this way compared to typing it on a computer or looking at bought books/printed "sheet music".