This document should help point you at various useful bits of information.
This repository contains the port of NetSurf to the Frontier UI library. This isn't intended to become a proper port or for any serious usage and I don't intend for it to get in to the main project. I've used it more as a great way to test my Frontier and libgeek libraries and has already uncovered many many bugs and missing features so far.
That said, it may prove to be a useful way to run the NetSurf in SDL with a basic UI!
Read the Quick Start document for instructions.
Look at the existing front ends for example implementations. The framebuffer front end is simplest and most self-contained. Also, you can contact the developers for help.