Shoutbox

I'm going to try and learn to make some plugins, but the API is so confusing! (I'm Blonde)

Could someone post some sample code, just to send a message?
If it's not too much trouble I'd also like to know how to do some simple tags

(i.e. User types "Message: (!XMESSAGE)" and the plugin has message defined as Hello World, so the user actually sends "Message: Hello World")

Thanks a lot!

edit: oops! I forgot to say I'm using VB.NET