What exactly is the problem? Have you installed Ubuntu, but do not know your username and password?
To find out your username, open a terminal (applications > accessories > terminal) and type
whoami. The output will tell you your username.
If you are unable to login because you forgot the username and password you set when you installed Ubuntu, see this to find your username and reset your password:
http://www.psychocats.net/ubuntu/resetpassword
And welcome to the LQ forums!
how to get username and reset password on Ubuntu
