Sounds like your chipset isn't configured... I agree with Lawless. What kind of chipset are you running? nforce? Is your hard drive connected via SATA? When you installed, did you choose the correct SATA controller?

I would recommend rebooting into your install DVD and checking out these Customizations first... after that you'll have to rely on the terminal in your install DVD.

The file I've attached is MeDevil's kext to help get SATA drives to respond. To manipulate this you need to unzip this file and place it on a flash disk with a known name (I will use "flash" in this instance for the name of the flash drive and "Leopard" for the name of the drive you've installed to) and do the following in Terminal:

<b>cp -Rf /Volumes/flash/AppleNForceATA.kext /Volumes/Leopard/System/Library/Extensions/IOATAFamily.kext/Contents/Plugins/</b>

<b>chmod -R 755 /Volumes/Leopard/System/Library/Extensions/ && chown -R root:wheel /Volumes/Leopard/System/Library/Extensions/</b>

<b>rm -rf /Volumes/Leopard/System/Library/Extensions.mkext</b>

(each of these is all on one line with a space separating the ones that were split)
Then reboot your drive and try it out.

---