Shifting the energy in a house can be as simple as opening all the doors & windows & letting light & air flow through, sweeping out teh house as Kaz said... anythign that makes it feel fresher. Anything that makes it feel yours.

Smudge sticks are bundles of dried herbs (for cleansing, White Sage) You light the end so that it its smoking then take it from room to room, let the smoke drift throughout the house, in corners of rooms etc. You can find them at stores or markets (usually the kind that sell crystals etc) - if you have trouble finding them, PM me.