http://www.blackberryinsight.com
you can download google maps to your sd card, and then run GMaps without internet connection 
use this site to mark area you want to storage:
Map Creation Tool for MGMaps
then download this program to your pc, to get maps:
http://www.mgmaps.com/cache/gMapMaker-setup.exe
and then install Mobile GMaps form here(there is a version dedicated for BB):
Mobile GMaps – Download
and enjoy gps maps from sd card 
Installing 3rd Party Applications
Note: If you have a Mac OS X / Macintosh machine you should take a look to How to install 3rd party applications (Mac OS X).
There’s a whole exciting world of applications for your BlackBerry out there. Installing those applications is a pretty straightforward process, though there are occasional issues that crop up. If you do encounter problem, there’s usually an easy solution. This article will talk about the steps to install a new application, and then discuss the most common problems that people encounter.
There are two ways of installing applications to your BlackBerry. You can download the software over the air (OTA) using the web browser on your device, or you can install an application from your PC using the RIM Desktop Manager.
To install OTA, you must have a URL for the sofware you want to install. The URL will point to a JAD file somewhere on the Internet. After entering the URL into the browser on your BlackBerry, it will prompt you to verify that you want to install the application. Say yes, and if all goes well it will install on your BlackBerry.
The second method of installation uses the RIM Desktop Manager. Applications meant to be installed from the Desktop Manager come with two files: an ALX file and a COD file. First, connect your BlackBerry to your PC using a data cable. Once the device is attached, launch the RIM Desktop Manager. Then launch the Application Loader from inside the Desktop Manager.
Click the “Add…” button in the Application Loader and specify an Application Loader File(.alx). The application should now appear in the list of items to install. Follow the instructions from there to finish the installation and it should appear on your Blackberry.
Piece o cake. Unless it didn’t work. If you hit a problem fear not. There are things you can do.
“No System Software was found for your handheld.”
Lucky you. You’ve either upgraded your handheld OS, or gotten a new BlackBerry for your birthday. Either way, your Desktop Manager doesn’t know how to talk to your BlackBerry. It is lacking the device software for your model of BlackBerry.
You’ll have to download and install the latest device software and service packs from your carrier. To see which device software you have installed on your computer, go to the Desktop Manager Help–>About and click the Device Software tab.
“No additional applications for your handheld were found”
First, make sure the .alx file and the .cod file are in the same directory. The Application Loader uses both files to install to your BlackBerry. If that isn’t the problem, then upgrading the Desktop Manager might help. You can download the latest version from your carrier or directly from RIM: http://www.blackberry.com/support. More detailed information on this can be found at: BlackBerry Install Error: No additional applications designed for your device found!
Invalid Digital Signature
If you are running a BES BlackBerry, there is a setting in the BES that doesn’t allow the installation of 3rd party applications unless they have been signed. You will have to contact your BES administrator to change this setting.
A fatal error has occurred while updating your handheld’s software. Please try again. Unspecified error encountered [J:0×0000000A]
That (most helpful) error message appears because the application you are loading requires a more recent version of the handheld operating system than you have. You will need to go to your carrier’s website and download a more recent version of the OS.
Very helpful article, keep up the good work!
That was nice. Thank you for sharing this one.
thanks !! very helpful post!