If you mean,boosting volume,you might want to consider this free program http://members.home.nl/w.speek/wavegain.htm
Most audio editing programs come with a normalising function which will raise the decibel level of your audio track. But a bad recording will always be a bad recording.
both EAC (exact audio copy) and Audacity will normalize the volume (both freeware). I use EAC to normalize all my wavs.