I'm looking for someone reliable to look over a vacant house for six
months starting in January. Live in is possible but not necessary. Can
you steer me to a listing or or other resourecs to find such a service
or person?

Dear mschulman,

While I don't know of a service,  I happen to know
someone nearby who might be able to do that for you.

Contact Nancy  at this website - 
http://campaignsthatwork.com/about.htm#contact
I am sure she can provide some pretty solid references.

Best wishes,

Your TaxMama-ga

As a long term house sitter I can definitely recommend a new house
sitting website I've just found called MindMyHouse.com to help you
find a good sitter. This website is new but it already has hundreds of
house sitters in its directory who provide their house and pet sitting
services to home owners for free in exchange for staying at your place
rent-free. A bargain! There's all sorts of helpful information on the
site to help you search the directory and eventually decide which
house sitter would be the best one for you. Good luck!