Hi Colin, thanks for your advice. I got the Vantec enclosure and a Western Digital WD5000AAKS 500GB 16MB SATAII hard drive.
The combo worked like a charm
. I had to set the hard drive jumper setting to SATA150 for the eSATA to work.
On Vista, the drive was recognized immediately and I could see in my computer. But on my XP box I had to use partition magic to partition and format the drive first.