Yes - it's possible.
You need to add the fields to the newuser_signup.tmpl template.
Then in the adduser.php script - you'd need to add get_input calls for each field you added, and add the new fields to the INSERT statement (to store them in the database).
There's also a section that says "if all required info is not filled in, then we can't proceed", adding your variables there would make them required on signup as well.
For what you suggested, you could use the existing Name and Location filed and wouldn't need to add any addtional fields into the database.
