I have a SCSI drive that's on a separate card (Adaptec AHA something), and it requires that some ASPI drivers be loaded in order to access the SCSI hard disk. It comes with a bunch of tools to format and partition and stuff. Is there any possible way I can boot from this drive?

Sure, if the drive is a hard drive, and the host that you're using is bootable. Enable the host adapter's rom bios. Most, if not all, of the tools that you mentioned are contained in the rom bios of a bootable controller. A good place to start

All the utilities and drivers are separate software, I meant, I don't think I clarified that. I don't think the SCSI has a ROM BIOS that takes up address space or can be enabled. I don't see any ROM code below 1 meg for it, and the computer's BIOS doesn't detect that there is a BIOS for the SCSI card.

Check your adapter at the link above to see if it's bootable. Of the four or so Adaptec hosts that I have, the rom bios is entered by holding down the CTRL key and pressing A. This is also true of jumperless hosts like the 2940W. Obviously, if the controller doesn't have a rom bios, then you will have to use the hdd driver installed off another drive to gain access to the scsi hdd.