The following were helpful in determining tones-- similar to what Joe M posted.
The easiest way to determine tones is crack open those Minitor II pagers.
I use GoldWave's expression evaluator to generate 3sec/1sec tones using an equation such as this:
.5*sin(2*pi*x*t)*(step(t-.1)-step(t-1.01)) + 1/(1+t)*sin(2*pi*y*t)*(step(t-1.02)-step(t-4.02))
where 'x' is Tone A and 'y' is Tone B, both in Hz. If you're ambitious (or silly), you can play it by ear-- literally, and compare the knowns from the list to a recorded sample. I guess Eric's method with Audacity would get you close (with Goldwave anyway) as I came up with about 2439 Hz when it should have been 2575 (unless the HT1250 used to generate it was off some).
Here's East Brunswick's as an example:
Fire (33.820 Mhz)
General Fire Tones: 2575 Hz (#33) / 910 Hz (#23)
Dist. 1-- Old Bridge Volunteer Fire Dept: 2575 Hz (#33) / 1082 Hz (#13)
Dist. 2-- East Brunswick Independent Fire Co: 2575 Hz (#33) / 992 Hz (#11)
Dist. 3-- Brookview Volunteer Fire Co: 2575 Hz (#33) / 1180 Hz (#15)
EMS (150.950 Mhz)
Standby (AKA Primary, "Night Crew"): 2575 Hz (#33) / 2361 Hz (#31)
General: 2575 Hz (#33) / 1403 Hz (#19)
Officer: 2575 Hz (#33) / 2807 Hz (#35)