I have not created any Sims 2 skins, but there are plenty of nude Sims 2 skins available for free download.  The nude skins I use were downloaded from a couple of other websites.  Two of the best resources for nude Sims 2 skins are:

http://www.x-sim.com/

http://www.mandmneedfulthings.ca/

Of course, all my female Sims characters are devoted naturists.  I wouldn't want to play them any other way.

In my Sims 1 game most of my male characters were naturists as well, but in Sims 2 males present a problem.  Skin editing and creation is much more difficult in Sims 2 than it was in Sims 1, so making or finding a realistic male skin (i.e. with a three dimensional penis) is something I have not been able to do.  Rather than deal with having to look at castrated "Ken" figures, I normally leave my male characters clothed and concentrate on playing the females.  The guys (the dutifully dressed breadwinners) have to spend their days at work, and it's the women who get to play.