cant understand what u realy need.... i am giving to option 1 for data monitoring 2nd for bill monitoring....
use bandwidth monitor.... gr8 tool doesnt eatup ur system resources.... it will tell u year by year, month by month, week by week, day by day, hour by hour data trancefar history, avrg speed... will warn u if u r crossing data limit (which u have to config it..).... visit the site to know more & to download the software....
www.bandwidthmonitorpro.com
next is to monitor ur bill... but u need this in dialup.... but as u asked for hours monitor then this might help u....
its called online meter.... u can config it to monitor ur bill.... gr8 tool tooo....
try this link....
www.webutils.com/om
but do reply with exatly what u need...