To get a list of all that information you should implement (or find an implementation) the SMB protocol used by Microsoft Networks. Linux uses Samba to comunicate to Microsoft computers.
SMB, which stands for Server Message Block, is a protocol for sharing files, printers, serial ports, and communications abstractions such as named pipes and mail slots between computers.
For more information about SMB look here.
For a list of online users you should query the server of a list of current users and then request each IP address seperatly.