Basic electrical questions.

Please pardon my basic electrical questions but i want to make sure i set up my system properly. I understand that dedicated lines are preferred for audio systems because the signal is cleaner. Does this eliminate the need for a line conditioner? Also, some people say they have separate dedicated lines for each component. I'm assuming then each component would plug directly into it's own wall outlet receptacle. If this is the case, how would a surge protector be used? Wouldn't it be better to plug the components directly into the surge protector and then the protector into the wall? And finally, i've read that amps should be plugged directly into the wall, but the outlet and circuit should be 20 amp. My amp plug is a 15 amp. Are there wall outlet configurations that accept 15 and 20 amp plugs, or would i have to change out the amp plug to a 20 amp? Well, that's it. Hope i didn't confuse anyone!