You need to actually 'Erase' the new HDD to format it HFS+ (journaled) so that OSX will install on it. Here's how you do it:
Step1
Open the system drive, usually titled "Macintosh HD." Open Applications, then Utilities and double click the "Disk Utility" program to open it. A window will open giving a list of all the drives currently mounted on the computer.
Step2
Select the disk that needs to be formatted on the left. It is not possible to format the startup disk unless the system has booted from the Install Disk. It is important to note that formatting the startup disk will permanently erase the data stored on the disk. If you are planning on erasing the startup disk, back up all important files and applications.
Step3
Click on the "Erase" tab to the right of the list of drives. The window will now display the options for erasing the hard drive and formatting it to work on the Macintosh computer.
Step4
Select the Volume Format from the pop-up list. In most cases it's best to leave it at "Mac OS Extended (Journaled)" as this is the default. This setting is the best option for running Mac OS X. If there are other requirements for the disk, then select the format that best suits your needs. If you have questions about the formats, refer to the Apple user's manual.
Step5
Name the hard drive. Type a name for the disk in the field where it asks for the name. This name will always appear when the disk is mounted on a Macintosh computer.
Step6
Click the erase button. A window will open asking to verify the erase procedure. Click the erase button in this window to start the process of erasing the disk. Once the process is complete, the drive will appear with the name it was given on the left side of the window with the list of drives and on the desktop of the Macintosh computer.
If you still want to take it into the Apple Store, they might have a USB to IDE cable so they may be able to work with the HDD alone. I dunno. I'd say give them a call before you go.
