Okey, it is /plugins and maby you have a plugin that is not allowing you to type /plugins or /pl, or maby you have craftbukkit.plugins disabled on your server (just if you use have a permissions plugin)
Dynamap
Okey you cant install a Dynmap to a wordpress site!
dynmap is hosting with your server (Minecraft) and it use your server ip :8123 i think! but i make your server lagg if you do something wrong!