The TeX Users Group published a formal(ish) workflow for converting LaTeX documents to ePub. It's similar to rkomar's workflow: convert TeX/LaTeX to XML via TeX4ht and then convert that to ePub.
I've had good results converting HTML to ePub with Calibre's ebook-convert:
Code:
ebook-convert in.foo out.epub --remove-paragraph-spacing --max-toc-links=999 \
--flow-size=9999 --output-profile=tablet --title="Foo"
Season to taste. I use the tablet output profile because I have large-ish readers (Kindle DX, Aura One).