Classical and Quantum Gravity - A journal for physicists, mathematicians and cosmologists working in the fields of gravitation and the theory of spacetime. (via IOP Publishing: Electronic Journals)
Inertia Manipulation Through Metric Patching - Presents the exact solution for the stress-energy tensor of a spherical matter shell of finite thickness that will patch together different metrics at the boundaries of the shell.
Living Reviews in Relativity - A peer-refereed, solely online physics journal publishing invited reviews covering all areas of relativity research. Published by the Max Planck Institute for Gravitational Physics (Albert Einstein Institute), Potsdam, Germany.