When i am running rcmysql start command it is giving me error that

Starting service MySQL warning: /var/lib/mysql/mysql.sock didn't appear within 30 seconds

and it is not starting sql services.Is there any solution for this problem as i am not able to create new sql users accounts also.I want to change root user password for mysql and also want to create new users but everytime i am facing this error so please help me to resolve this problem.

Check the logs, you will see why the service is not starting.

check your logs, if you can't resolve the problem, post back those logs and "my.cnf"(mysql config, usually in /etc/mysql).

I found these lines in log files

InnoDB: Unable to lock ./ibdata1, error: 11
InnoDB: Check that you do not already have another mysqld process
InnoDB: using the same InnoDB data or log files.
100109 1:10:43 InnoDB: Unable to open the first data file
InnoDB: Error in opening ./ibdata1
100109 1:10:43 InnoDB: Operating system error number 11 in a file operation.
InnoDB: Error number 11 means 'Resource temporarily unavailable'.
InnoDB: Some operating system error numbers are described at
InnoDB: http://dev.mysql.com/doc/refman/5.0/...ror-codes.html
InnoDB: Could not open or create data files.
InnoDB: If you tried to add new data files, and it failed here,
InnoDB: you should now edit innodb_data_file_path in my.cnf back
InnoDB: to what it was, and remove the new ibdata files InnoDB created
InnoDB: in this failed attempt. InnoDB only wrote those files full of
InnoDB: zeros, but did not yet use them in any way. But be careful: do not
InnoDB: remove old data files which contain your precious data!
100109 1:10:43 [ERROR] Can't start server: Bind on TCP/IP port: Address already in use
100109 1:10:43 [ERROR] Do you already have another mysqld server running on port: 3306 ?
100109 1:10:43 [ERROR] Aborting

Mysql is already running stop it first before starting.