Welcome to Cyber Nations!
Are you interested in alliance based or nation based role play? Are you more interested in dealing with macro level (Cyber Nations) politics or on the micro (individual nation) level?
Alliance Based
Deals with the events surrounding alliances (peace, wars, treaties, etc).
Nation Based
Deals with the events surrounding individual nations (tax collections, sanctions, national anthems, etc).
Macro Level
Deals with the overall politics and layout of the game.
Micro Level
Deals with what is happening within the individual nation.
In general, the [url="http://forums.cybernations.net/index.php?showforum=69"]Open World RP[/url] forum is where you find most of the Macro Level discussions. Discussions here are on issues that can potentially affect everyone. The [url="http://forums.cybernations.net/index.php?showforum=70"]Alliance Announcements[/url] is where alliance level politics take place while the [url=http://forums.cybernations.net/index.php?showforum=71]World Affairs[/url] forum is where you find conversations about the overall game client as they relate to the nation level. So by the terms I defined above, the Alliance Announcements forum is Macro Level Alliance Based and the World Affairs forum is Macro Level Nation Based.
The [url=http://forums.cybernations.net/index.php?showforum=72]Open National RP[/url] forum is where what many people would recognize as "role play" takes place. This is the forum where people write long stories abou their nation and interact with other players. [url=http://forums.cybernations.net/index.php?showtopic=69861]This thread[/url] gives a great overview of how to take part in that role play. Discussions here don't necessarily reflect the layout of the actual game as there are often people who are in different CN alliances deciding to be allies in their RP game. Again, by the definitions above, the Open National RP forum is almost entirely Micro Level in scale but can be Nation Based Micro Level or Alliance Based Micro Level.
It sounds like you're more interested in Micro Level RP. There's no set go to guy for that but I'd suggest contacting some of the actives and asking them to get started. In looking at the first page, Kaiser Martens, Centurius, Triyun and Voodoo Nova have been playing for a long time and may be good people to ask.