Beginning with Outlook 2000, you can map your contacts address using MapPoint installed locally or Microsoft's online mapping service. Due to recent changes at the Office website, online mapping is broken in Outlook 2000, but you can restore the capability with the online map server of your choice by editing the registry.

To edit Outlook 2000's registry, from the Start menu, Run command, type regedit and press Ok. Navigate to
HKEY_CURRENT_USER\Software\Microsoft\Office\9.0\Outlook\Options\General

Right click in the right pane and choose New, String Value. Enter MapScriptURL for the string value name. You have at least three choices for the data value:

MapPoint:
http://mappoint.msn.com/home.aspx?strt1=<0s>&city1=<1s>&stnm1=<2s>&zipc1=<3s>&src=OL&o1=<0s>&o2=
<1s>&o3=<2>&o4=<3s>&o5=<4s>

Yahoo Maps:
http://mappoint.msn.com/home.aspx?strt1=<0s>&city1=<1s>&stnm1=<2s>&zipc1=<3s>&src=OL&o1=<0s>&o2=
<1s>&o3=<2>&o4=<3s>&o5=<4s>

Map Quest:
http://www.mapquest.com/maps/map.adp?address=<0s>&city=<1s>&state=<2s>&zip=<3s>

Outlook 2002 uses MapPoint by default, however you can add the registry key if you want to use a different mapping service. (Outlook 2002's registry path is Office\10.0\Outlook.) Attempts to use this key with Outlook 2003 cause Outlook to crash.

More information