Importing Addresses in Netscape
If, when you attempt to run, File-Import from Netscape's address book
program, you get the message, "Application not available" or something to
that effect, you need to install the import utility. To do this, go to
ftp://ftp.netscape.com/pub/communicator/smartupdate/english/windows/windows95ornt/4.5 and double-click on import_utility_32_45.jar. This will run a java program that will update your version of netscape with the import utility. Note that for this to work, you must have Smartupdate enabled. To do this, go to Edit-Preferences, then Advanced-SmartUpdate and make sure the box next to Enable SmartUpdate is checked.
If you want to export an address book, you do pretty much the same thing, but choose File-Export. When it asks what type of file to create, .ldif usually works the best. If this fails, choose .csv as this is just a list of comma separated values, which should also work just about anywhere.