To create a new model in your module Add a folder Model
in your module root folder and create a file Modelname.php in this folder.
for example Rick/Demo/Model/Modelname.php
The class name of your model does matter call it like this:
<?php
class Rick_Demo_Model_Modelname {
}
make sure your model is defined in your config.xml
in the etc
folder of your module
Here an example:
2.0.4 Rick_Demo_ModelTo load your module use the following code:
Mage::getModel('customemodelname/modelname')