What kind of harddrive do I need for xbox

Kellmira, the original drive is a ST310014ACE SEAGATE 10GB 3.5 INCH IDE HARD DRIVE. You can still get these on ebay.com. All you are really looking for is a 5400RPM 3.5inch IDE drive, but you can not simply add a new drive. It is "married " to the motherboard, so you would have to try to either clone your old drive, or get the hard drive key of your xbox. There are numerous tutorials online, this being one of the better once. If you take a look around you could also replace the PCB on your existing drive, for as long as it does not have a mechanical failure, then use a new drive and clone it. Use this guide to replace the drive. Hope this helps, good luck.