From MesoscopicWiki
For some quick background material on the basic models of permittivity in metals, insulators and plasmas, I find that Section 7.5 of Jackson's Classical Electrodynamics is quite useful.
Here is a great set of lectures by Steve Johnson at MIT., who happens to be one of the developers of the MEEP ab-initio code.
Simulated results
Wave propagation through a lattice of SRRs
Wave propagation through a LHM composed of symmetric E-shaped structures
Spatial dispersion papers by Agronovich and colleagues