Our friend IRIS (Incorporated Research Institutions for Seismology) comes through with a posted activity,
This exercise refers you to the QCN site at Stanford which allows you to download software. The software not only works with a Mac laptop (2006 or later), but also a Thinkpad (2003 or later), or a desktop with a USB sensor.
In addition, you can purchase an external USB accelerometer (for Macs, PCs and Linux) can be purchased from the Quake Catchers Network (request a sensor on right hand menu).
(Or, buy a Macintosh!)