(not a commercial CD). I did some recordings of a band years ago and ran into one of the band members who asked me if I could make copies. I assumed that this would be easy. I know that I can rip the CD into iTunes and then burn a new CD, but I have two optical drives available, is there a way to simply copy the CD from one drive to the other in one step?
You can do this with Burn, and free and open source tool for Mac:
Not exactly a "single-click", but I can assure you it's very simple to use.
When copying audio CDs I highly recommend ripping to hard disk first. The reason is quality control - ripping audio to disk allows your application to use error detection & correction mechanisms that a straight disc-to-disc copy won't perform. Additionally, it gives you a chance to play the tracks and make sure the rip is correct. Especially for scratched CDs, you really want a secure ripping program to help you get the best copy possible.
In iTunes, rip to Apple Lossless or AIFF or WAV formats for best results (other formats encode the data in a lossy format that loses quality).
Other ripper programs include Roxio Toast, Max from sbooth.org, and the open-source Burn that other answers have mentioned. OSX's built-in Disk Utility is not recommended for copying audio CDs. If you want EAC-like quality (perfect rips of even the most scratched discs), Max seems to be highly recommended.