AC Power Line Conditioners

I am very interested in finding out more about power line conditioners. I have a friend who has a Macintosh system and Monster 5100 power line conditioner. He plugs his MC 2500, CD player, Pre-amp and turntable into this line conditioner. I always thought power amps needed to be plugged straight into the wall as most power line conditioners cannot handle the high current, power, etc.

My music taste range from classical to jazz records (orchestras, bands and choral)and CD's. I will also be playing R2R 15ips tapes.

My questions are these:

1. Generally how should I go about picking a power line conditioner that does not restrict the music.
2, What do I look for regarding protection from lightening strikes, thunder storms, etc.
3. How much should I consider spending on the line conditioner?
4. Should I stay away from the Monster line conditioners which I would think is more for Home Theater Systems which is not my present interest.
5. Please provide the names of several line conditioners so that I can do the research and learn more about them. Thanks much for all input.