Welcome to the forums,
The edit button grayed out usually means you just have viewer permissions (rather than manager or admin). When you create a new contact it shouldn't let you select the shared address book in the drop down on the right under job/company.
Black strike is usually a deleted item. Did someone else move it to the trash? (Though it's interesting that you'd even see it at all then, unless they shared the trash folder with you as well).
What version is this? Type this in the AJAX client search bar: