Yes. Whether you manually or automatically add someone as a Lead or a Contact, it'll show up in CRM reports under their respective columns.
To track your Leads and Contacts:
Go to Reports on the left-hand side panel, and select CRM under Standard Reports. The first thing you'll see is the Leads Created tab. You can view details such as Day, Lead Name, Lead Owner, and Lead Source. Similarly, the Contacts Created tab will show you details of your CRM Contacts.
Click Lead Source filter located in the top-right corner of the report to view which social networks your Leads and Contacts were generated from.