You can find plugboards to add your plug to by doing a Google search. I only add mine to ones that are family friendly and don't require a link on my website back to their site. Since my plug is for my Etsy shop that would be impossible for me to do.
You can make your own plug using a photo editing program or you can search Etsy for sellers that will make a plug for you.
If you would like to add a plugboard to your blog or website you can create one at http://www.plugme.net .