I've been doing further homework on enclosures and found these guys:http://www.pc-pitstop.com/sata_enclosures/
They are a lot cheaper than MacGurus, and use a lot of the same component, also provide great phone support.
Most enclosures are provided by one company - Cremax... and PC-Pitstop, MacGurus, etc... take them and repackage them.
They have the host card for PCIx for $99 (for MAC - but must call - not on their site); Port Multiplier cable (1meter) for $8 bucks, and a 4 port External hot swap bay set up with Port Multiplier for $289 - same enclosure as MacGurus sell for $369...
If anyone has seen a better deal with better service, or had any problems with PC-Pitstop, please post.
Found the 750 Gig drives at FRYs for $299 too as of Oct 4, 2006