I've attached a scanning site that has the most current info you may be looking for. Click on NH and find the counties you are interested in.
By the way, most of the law enforcement agencies you may be wanting to monitor have or are in the process of converting to P25 digital transmission. What this means, if you have the typical analog FM scanner, all you will hear when attempting to monitor those channels is a digital "buzzing" noise.
You can get a P25 capable scanner at any Radio Shack (the PRO-96 handheld). You can also purchase the Uniden handheld (250D or 296D) or Uniden base/mobile (750D or 796D). The 250D or 750D need an additional digital decoding card. The PRO-96, 296D & 796D all come fully digital capable. The Unidens can be ordered from a number of internet resources, or via Ham Radio Outlet on Route 28 in Salem, NH (an excellent source for scanners and scanner info).
Expect to pay around $500 for any of the aforementioned units.
The fire & rescue-ambulance services are still analog. However, many Fire Departments are now receiving Motorola ASTRO P25 digital radio equipment. While it will be a long time before these agencies convert to full digital operation, many will operate sporadicaly in digital (i.e., non-emergency traffic on their local town government frequencies) mode when their departments receive enough radios to operate in this mode.
In closing, as the previous poster has offered, please feel free to contact me anytime via e-mail for specific frequency requests or scanner equipment questions. I would be glad to help out.
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