I'm trying to write something with two columns that spans multiple pages.
I want to put one thing in the left side and one in the right side. Is there ``proper'' way of doing this, or should I just try and bodge it with tabular/table?
Looking at CTAN by Topic I've found reference to
parallel: Provides a parallel environment which allows two potentially different texts to be typeset in two columns, while maintaining alignment. The two columns may be on the same page, or on facing pages.
parcolumns: Provides an environment for typesetting text in two or more parallel columns (as for example, in a multiply translated text)
paracol: The package provides yet another multi-column typesetting mechanism by which you produce multi-column (e.g., bilingual) document switching and synchronizing each corresponding part in “parallel”.
parrun: For typesetting translated text and the original source, parallel on the same page, one above the other.
I've never used them but I hope some of them will suit your needs.