I still have 2 questions

1) Now that my admin page has come up and I am able to login into it, what next ? Is there any guide apart from FAQ's section which can guide me how to start working in the admin panel and where to start from ?

2) Even now, if I am typing in the browser, www.mydomain.com

I am getting an error page saying " Index of
* catalog

Why would this happen, few minutes when I was typing www.mydomain.com it was taking me to a page www.mydomain.com/catalog/index.php and was showing me the basic green color zen page with all the dummy data and text etc. But not I am getting this index of error message.