Ok, extract the zip into a directory (say, /usr/src/ideraid). Go to that directory and attempt to compile the driver by typing make.
Your going to need to make sure you have the kernel source package installed for your running kernel as well as the development tools. Seeing as your a Debian user I'm going to assume you fit that criteria.
If it compiles cleanly then all you probably need to do is a make install, or copy the .ko file created to /lib/modules/<your kernel version>/kernel/drivers/ide or something like that and try and load it.