Burn some sage.

There is a thread I started in the Paganism board about cleansing our house, some fab ideas in there

I would also be inclined to do something outside too.
Get some white sage if possible. Also, ring a bell in the rooms to help cleanse it. DH & DD1 had to do a cleansing in this house when we moved in in Sept - I oculdn't do it because burning sage is a no no in pregnancy. I couldn't walk into the house without feeling someone here who wasn't happy to have us here. The cleansing helped HEAPS but time has helped also. We get the occasional thing happen but it doesn't make us feel uncomfortable anymore.