Welcome to the forum
You will be added to the reseller forum in due time by forum admin (either Matt or Tom). This doesn't take very long and doesn't mean you are served any less well support wise while you wait for your access - the reseller forum isn't mainly for support but chat between forum members about reseller specific stuff. If you have a support issue you want to ask about feel free to use the dedicated support forum.
Given what knows if you are a reseller or not (the billing system) and what gives forum permissions (vbulletin software) what you propose is actually not quite as straight forward as getting the two systems to talk to each other requires plugins to be written for both systems. Its far easier just to offer access to any reseller who asks for it.