if you paid 500$ for your laptop... well... consider urself lucky
I bought a 2200 laptop
depending how much you use it.. it will die that much faster you have to remember its a portable device not a desktop..
if you leave it on 24/7 and constantly leave it plugged in or drain it, it will last about 12-18 months.. with 'constant' use..
ever heard the saying 'give them the razor charge them for the blades'? LOL
batteres run about 100$ of if you don't want to be portable just plug it in to the wall with an A/C Adapter.. (i'd recommdend this if your not going to be using it in a mobile status