When I bought my templates, they all had the little copywright symbol and a company name in the footer, so I just put in my website's name even though I never had anything copywritten. Is that legal?
Check with the terms of service of the original developer. Normally a "template purchase" has an implied transfer of copyright (but without a exclusive transfer the developer can continue to sell the template to others) meaning you can do as you which on your purchased property.
Right, but don't I have to like fill out a form with the government or something to copywrite my content? So since I haven't done anything like that, then I don't want to get in trouble for saying my stuff is copywrite but really isn't. Or do you just copywrite it by saying so in the footer?
As long as the content is original it's copyrighted by defualt in the U.S. You don't even need to put the (c) it's still copyrighted
You don't need to fill out any form to place a copyright statement on your site. As Dabontv stated it isn't even needed legally; however, it is a good idea to use a copyright statement on your pages to prevent confusion and reduce the likelihood that someone would "innocently" copy your content under the guise that it was in the public domain.
You are talking about two different things (I assume). The "template" was designed by someone so until you purchased it the copyright of the designed was under their common rights. No matter what the original designer is the only person that can make a claim to copyright on another person or firm e.g. someone say not paying but using their design... you cannot make an claim on "template design" unless the developer (in writing) transfers these rights to you. This however, does not prevent you from including your copyright mark on the design from the content contained within the design shell. As for "content" e.g. page information not directly associated with the design template itself - has a common copyright claim by you (provided you wrote it). If you need - it is always advisable to register but you do not need to.