Garmin today announced a new GPS plan for BlackBerry users called “Garmin Mobile for BlackBerry.” The software will allow customers with GPS-enabled BlackBerrys to use Garmin GPS software for a one-time $99.99 payment. If you don’t have a GPS-enabled BlackBerry, you can use an external device, such as the GPS 10x, a portable GPS sensor that will communicate location data to your BlackBerry via Bluetooth. Garmin Mobile will provide BlackBerry users with voice-guided turn-by-turn directions, weather, traffic information, and gas prices. Users can also use the software to find points of interest during trips, including local restaurants or entertainment destinations such as bowling alleys and more. The software will also reroute you, should you miss an important turn while you’re driving, no thanks to the screaming kids in the back of your 1996 Chevy Astro. One aspect of the software that could cause some confusion is its approach to providing data. The maps are stored online and not on the device itself. And while Garmin suggests this is great for always having up-to-date information on accidents, detours, and gas prices, it could also result in some confusion if your phone loses a signal for an extended period of time on the trip. With most GPS software costing as much as $9.99 per month on AT&T, Sprint, and Verizon Wireless, the sub-$100 deal sounds like a steal, especially considering that $99.99 will only get you 10 months on those plans. You can grab the software from www.garmin.com/mobilephones, and it’s supported on the 8310 and GPS-enabled 8800 series BlackBerrys.