Installed a new internal hard drive and when I try

Boot off the install disk with nothing else attached to the PC. ( external hard drives especially ).
Choose ‘Terminal’ in the ‘Utilities’ menu
Then (substituting the correct values for your setup), type:
diskutil partitionDisk /dev/disk0 1 GPTFormat JournaledHFS+ my-hard-disk 111G
It’s all one line and hit return at the end.
You should see progress information, followed by a neat table giving the new formatting that has been applied.
‘/dev/disk0’ is how the operating system refers to the first whole disk in the system.

Then, the ‘1’ here signifies that you want one volume only on the drive.

Then, replace ‘my-hard-disk’ with the volume name you want to use. This is the name of the disk as it appears in the finder.

Replace ‘111G’ with the size of the disk in gigabytes. It’s usually about the same as the disk, and as the partitioning software will stretch a single partition to fill the disk it doesn’t matter too much. 111G was the value used for a 120GB HDD, because I knew that it wasn’t really 120GB.

Hope this is of some help.
If not a solution ( hard one to do over the net :) ) hopefully it will point you into a solution.

I would try booting with your Mac OS disc and when you get to the dialog box to install Mac os, instead find the Disk Utility in the upper menu.
Attempt to mount the new drive thru Disk Utility. If it doesn't show up, it may be that the ribbon cable didn't get connected properly when you installed it. You may need to open it back up to check your connections...
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