I have ordered the new iMac and Apple has removed the disc drive from the computer. How will I install my Virtual Drumline onto this computer?

If you're already using a Mac then Migration Assistant is the best way to start. In cases where you need a disc to install or for verification, use the drive in your other Mac. Just as you can remote access computers or hard drives on a network, it is possible to use the disc drive remotely. I've had to do this several times when installing software on my wife's MB Air. It's simple and straight forward.

I had a PC so this still worked. Just installed the software from Apple to do so.