As alex_ant pointed out, Lacie is not a brand of hard drive, they use HDs from other manufacturers such as Seagate and WD.
Personally, I would agreee with alex_ant and recommend going with a hard drive enclosure instead. You pay a lot for an external hard drive, sometimes 50% over what you would pay for the same capacity drive as an internal drive. With the ever-increasing capacities of drives and the ever-decreasing costs/GB, I think it is most cost-effective to buy the enclosure and the internal drive. Then in a couple years when 500 GB drives are the same price as the current 100 GB models, you'll be laughing.