Power Strips

As a starting point, an audio-grade power strip with surge
protection is what I used. The important thing is to
physically isolate the power cables as a group from
interconnect and speaker cables.

For an HT, you might consider Monster HTS 1000 or 2000 (or their successor models, if you buy new).

The least expensive surge-protector (not power conditioning) that will not make the video or sound worse is the Vansevers Companion at $30.

I do think conditioning is a good idea, more for video quality than sound. My favorite budget conditioner that will make the video sharper and clean up the audio some is the Audio Power Pack II ($239 at AudioAdvisor.com and elsewhere).

You should consider the purchase of a Monster Cable HTS 2000 power center. It is a power conditioner/surge protector which retails at about $200. You can buy it cheaper on ebay and you may be able to get it here also. There are others that may be better but this one gets high marks at a good price point. Get it from an authorized dealer if the $100,000 conected equipment warranty is important to you. You will see immediate improvement on video. Audio will take a few days to break in.