Looking for a Simple Anti Grief

Im not quite sure where to post this, but aren't there any Anti Grief plugins which allows you to select a block not to be grief and to be griefed.
Like imagine im standing on a obsidian block I could right click it to not be griefed and left click to un- Anti Grief it. Please help me out.

 

Well you could use worldguard, that's the first thing that comes to mind with the description you provided

 

Is there a way to get started with making Plugins, when using plugins such as world guard aren't there any source codes I could learn from.

PS : Thanks for the information. !

 

Wether or not the plugin is open source is up to the developer, usually it will say so in the post for it. And as for a way to get started, download and setup eclipse and the JDK plus the bukkit api and start coding, there's a good guide in the wiki for how to start (can't link cause I'm on my cell phone)