range in home

Hello,
I don't know much about wireless, but am learning some things. It's very confussing to me on how I can get more range in my home. I'm not hooked up to any router or anything. I just get a signal from a repeter down the street. Our little town has access to this antenna, but I only get the signal in certain areas of my home. I would love to move around freely. I don't think I can do this with out get another antenna and conecting it to a bridge then a wireless router. Am I right??
If I have to is there something I can just plug in to the wall and then run a cable to my laptop???
Any help would be wonderful.
thanks, Vicki
I have a powerbook g4