/etc/skel is the template which is copied to form the initial content of a new user's home directory. I seriously doubt you want to store anything there.
Sounds like you want /in/username to access ~username/html (i.e. the html subdirectory of the specified user).
Part of this is actually pretty easy. Just make sure mod_userdir is loaded. Then, place this configuration directive somewhere:
UserDir html
This will make requests to
http://server/~username/index.html access ~username/html.
The problem here is that it's not exactly the URL you want. You can use mod_rewrite to patch that up.