Six 6.5-cycle test tones for CEA-2010 measurements, spaced by 1/3rd octave. These are great for testing subwoofer distortion and output. You can watch the results on a real-time analyzer, or just listen, because distortion is easy to hear with these.
63 Hz    50 Hz    40 Hz    31.5 Hz   25 Hz    20 Hz

Stepped deep-bass subwoofer test tone described in "Subwoofers: 4, 2, or 1?" Consists of sine waves in 1/6-octave steps from 20 to 80 Hz at -15 dBFS peak. NOTE: As with any material containing intense low-frequency signals, exercise caution with your subwoofer level setting when you play this tone. Playing it too loudly can overload the amp or damage the driver. If you hear distortion, reduce the level.

Pink noise at -18 dBFS. Play this and view the result on a real-time analyzer (RTA) to see how flat the response of your system or subwoofer is in your room.

Sub crossover test tone in 1/6th-octave steps from 40 to 140 Hz at -18 dBFS (40-45-50-56-63-71-80-89-100-112-125-140 Hz). To test your subwoofer crossover settings, play these and measure the level from your listening position using an SPL meter. Adjust the crossover frequency and subwoofer phase control so that the levels of all tones are as consistent as possible. (It won't be perfect because of the acoustics of your room.)

TrueRTA: Great spectrum analyzer software for DIY audio measurement
Harman Research: Lots of great audio papers
RightMark: Awesome free audio measurement software

The Audio Measurement Handbook: by Audio Precision, scroll down for free PDF
Don Keele's website: Still more great audio papers
Room EQ Wizard: Still more awesome free audio measurement software