Wiki [1] and OSDev [2] both have pretty solid articles if you want to know how to load an ELF into memory.

I used both when implementing ELF for my hobby kernel [3]

[1] http://en.wikipedia.org/wiki/Executable_and_Linkable_Format

[2] http://wiki.osdev.org/ELF_Tutorial

[3] https://github.com/lexs/rust-os/blob/master/rost/exec/elf.rs