If you ever needed to create a custom Customer tab and put some information there, as well as submit a form, this should give you enough information to accomplish this task.
Create Module declaration
app/etc/modules/Russellalbin_Customertab.xml
<?xml version="1.0"?>
<config>
<modules>
<Russellalbin_Customertab>
<active>true</active>
<codePool>local</codePool>
</Russellalbin_Customertab>
</modules>
</config>
Create the module configuration file