I signed into Familysearch.org and was unable to find how to get into Family Tree as you described. New.Familysearch.org requires you to be LDS. A search in Familysearch.org under Family Trees brought up items from Ancestral Files and Pedigree Resource with no indication that they could be edited, sourced, etc. Where to I need to go to access what you described?I will try to be as specific as possible.
Family Tree is a user submitted program seeded by data from New.FamilySearch.org. New.FamilySearch.org has had limited access, especially to those who are not members of The Church of Jesus Christ of Latter-day Saints. Family Tree, on the other hand, is available to anyone who registers for either an LDS Account or a FamilySearch Account. Access to all of the FamilySearch.org resources is entirely free.
You can follow the instructions below to sign in and register, or you can click the Sign In link in the upper right hand corner of the FamilySearch.org screen and follow the instructions.
Family Tree is available through a link on the FamilySearch.org website, but you have to initiate the link before it will appear. The instructions for gaining access to the program on a PDF file called Gaining Access to the FamilySearch Family Tree (pdf). Here are the instructions:
1. Go to http://www.familysearch.org/invite/familytree_tab.Please feel free to post additional questions about this topic.
2. Enter the required information in the fields provided.
Important: When you enter your user name and password, enter the same user name and password that you use on familysearch.org and new.familysearch.org. This lets you see your FamilySearch Family Tree and all of your changes as they appear in new.familysearch.org in the FamilySearch Family Tree.
3. Click Register.
The FamilySearch FamilySearch Family Tree appears. You are in the main position on the screen. To get to the FamilySearch Family Tree from now on, go to www.familysearch.org, and sign in. The link to the Family Tree appears in the upper-left corner of the screen, next to the FamilySearch logo.