Look in the following directories:
{CodeWarrior Installation}\DSP56800x_EABI_Tools\command_line_tools\ and study the contents of mwld56800e.txt. This has information on using the command line linker and its control switches. The -srec switch should generate a S-record file for you.
In the {CodeWarrior Installation}\Help directory, look for the Build Tools Reference manual (56800x_Build_Tools_Reference.pdf) and check out the chapter, Using the Build Tools on the Command Line for more information.
---Tom