Use this forum!
When I was preparing to travel, I simply used this forum to find a flying field. This worked out best for me because I was able to find out which clubs were friendly to flying guests and which ones weren't.
RC_SPORT invited me to his field (as did members of two other clubs there). Unfortunately the weather was so lousy that no one flew. It was nice to meet members of their club though, and now I know when I'm "lucky" enough to visit my inlaws, I've got a place to go.