If you have old records or cassettes that you want to digitize, but don't know what to do about the noise, here's your answer: Izotope RX2. There are definitely cheaper, and darn worthy alternatives such as Bias's SoundSaver and Cakewalk's pyro Audio Creator 1.5, but RX 2 astounded me in my tests for PCWorld's "Digitizing Your Life" feature. One click of a button and my test recording of an old LP was free from clicks, crackles, scratch noise, and other background noise--without any appreciable loss of high end. Highly recommended if you have the cash. RX 2 is also available on the Mac.
Note: This link takes you to the vendor's site, where you must register to download the software.
--Jon L. Jacobi