Felicia,
The registration page you posted looks to have a PHP error on it. That's why the rest of the template isn't rendering. If you go into the Global Configuration area of Joomla, you can set Error Reporting to Maximum and that should help locate the problem with the changes you made.
Before we get into the other Login page from JomSocial, let's fix the main registration page. If we take things one step at a time, things get less confusing and more focused, which makes for easier diagnosis of problems (and hopefully more experience in learning what's going on).
As for the default.php file you're looking for, that's called a template override. As stated in the post, you'll need to create that directory and copy the file from /com_user/views/register/tmpl/default.php to that directory. It won't be there automatically.
However, I don't think you need to make that change because you're using JomSocial anyways. That change is if you're using Joomla's registration process, not JomSocial. If you followed the instructions in the
JomSocial Integration Guide
for the Registration page, you created the template override that you need already. Just modify that file and forget about the other post you read.
Once you enable error reporting, hopefully that will help us narrow down the issue and fix that page. If you know the changes the made, you're free to post them here as well for us to see what might be wrong.
Regarding phone support, it's simply not possible. We already have staff in multiple timezones to be able to provide 24 hour responses to the forums. We've investigated what it would take for phone support to do the same, and to always be on call, it would require either a subscription rate of about $150 or an additional support fee of about $40-50 / hour. That's not something most users would appreciate. If this is beyond what you are looking for, we'd highly recommend having a developer on hand to help or be patient with our forum support. You can utilize us as much as you want, and your subscription is for 6 months. For $50, that's the best support you can buy.
Best of luck, and let us know how it goes,
Alex