Go look on Poor But Happy - they always seem to have a whole fleet of native English speakers looking for teaching and/or translating jobs (although I can't vouch for their competency, but I suspect that for many of them their confidence far exceeds their ability) and from time to time some native Spanish speakers wanting English speaking clients to teach to or translate for. Can't vouch for their competency either, but may be worth a try to put a posting over there or at least read through the archives.
