Get from https://github.com/PowerShellMafia/PowerSploit.
Then import it using
powershell-import .\PowerView.ps1

Get-Domain
or add -Domain for other domain.

Get-DomainController
Get the DC information.

Get-ForestDomain
Returns all domain for the forest or specify a forest with -Forest.

Get-DomainUser
Can use -Properties MemberOf to filter properties or -Identity anyuser to filter users.

Get-DomainComputer
Same can use -Properties DnsHostName

Get-DomainGroup
Return the domain group. Can use things like | where Name -like "*Admins*" | select SamAccountName to further filter the results.

Get-DomainGroupMember -Identity "Domain Admins" | select MemberDistinguishedName
Returns which members are in Domain Admins.

Get-DomainTrust
Get domain trust information.