How to publish my own msgs to topic?

edit

I am a beginner in ROS.My operation system is Ubuntu 12.04 and my ROS is hydro.After I read some chapters about the "talker and listener" of The Beginner Tutorials in ROS.wiki,I try to write a publisher to publish message to topic "turtle1/com_vel" so that I can control the turtle to run round.But when I try to make my code,it fails.The terminal reminds me that

  CMake Error at /opt/ros/hydro/share/catkin/cmake/catkinConfig.cmake:72 (find_package):
  Could not find a configuration file for package ros.

  Set ros_DIR to the directory containing a CMake configuration file for ros.
  The file will have one of the following names:

    rosConfig.cmake
    ros-config.cmake

I guess that there is something wrong with my CMakeLists.txt.But after comparing it with the demo in ROS.wiki,I still can't find the error. This is my code in cpp file.In this file,I define a publisher named move_turtle.

 #include "ros/ros.h"
 #include "geometry_msgs/Twist.h"
int main( int argc, char** argv )
{
  // initialization
  ros::init(argc, argv, "move_turtle");
  ros::NodeHandle n;
  ros::Publisher move_pub = n.advertise<geometry_msgs::twist>("turtle1/com_vel",100);
  ros::Rate loop_rate(10);
  //define the moving rule that I want.It is a circle.
  geometry_msgs::Twist com_cicle;
  com_cicle.linear.x=3.0;
  com_cicle.linear.y=com_cicle.linear.z=0.0;
  com_cicle.angular.x=com_cicle.angular.y=0.0;
  com_cicle.angular.z=2.0;
  while(ros::ok())
  {
    //publish the msg to topic /tuttle1/com_vel
    move_pub.pulish(com_cicle);
    ros::spinOnce();
    loop_rate.sleep();
  }
  return 0;
}

cmake_minimum_required(VERSION 2.8.3)
project(move_turtle)
 
find_package(catkin REQUIRED COMPONENTS
  ros
  geometry_msgs
  turtlesim
)
 
catkin_package()
include_directories(
  ${catkin_INCLUDE_DIRS}
)
## Declare a cpp executable
  add_executable(move_turtle src/move_turtle.cpp)
## Specify libraries to link a library or executable target against
  target_link_libraries(move_turtle ${catkin_LIBRARIES})