Christian,
If you talking about releasing code or software (I’m just guessing this may be the case from the link the FDL license), I would just follow the example that comes with any WordPress plug-in or WordPress itself. Most have a commented section of code indicating the license it’s released under, any conditions of use and terms of licensing a derivative work and simply stating that making use of the software indicates the acceptance of and agreement to the aforementioned licensing terms. Actually, following your own link to FDL is your best bet for more information on that.
If you’re talking about this in the context of a website, graphics or writings, then I don’t know how anything more than a simple copyright would be applicable. Keep in mind that I am Canadian, so intellectual property issues here seem much more logical and simplistic (generally speaking) than they are in other places. Creative Commons is an excellent resource for information and resources for licensing liberal arts type content.
If your going to be offering any type of services through your site, just make sure a link is readily available to the terms of use, indicate that registering, using or viewing any content, resources etc indicates ones acceptance of the terms of use and the only recourse to withdraw that consent or if they do not agree with the terms is to not use the service, basically “If you use it, you accept it [the terms TOS], if you don’t accept it, don’t use it??. Give these rather well-written (and understandable) terms of use for the CBC (Canadian Broadcasting Corporation) or just look for a similar website (i.e.: NBC in America, the BBC in the United Kingdom, etc) and review how they regulate their terms of use. I think a broadcaster is a good example for a blog as the offered services is somewhat similar. Add in the Creative Commons and the Free Software Foundation and I’m sure that covers all of your bases.
I hope this is what you were looking for or at least points you in the right direction!
Cheers,
Michael.
NOTE: Remember, this is not legal advice; all of this is extrapolated and interpolated from common sense and experience in policy analysis. See a solicitor if you require actual legal advice.