I want to start a brand new computer without all the 6 month trial software, i.e., Norton, Office, AOL, etc. Some retailers offer to deactivate these programs for a fee. Anyone know how to do this or a source for the procedure?

Wipe the hard drive of the computer. Install the operating system you want and the programs you want and you are good to go.
This requires you to buy the software yourself, but it's the simplest way to get a clean system.

   If you don't do what dlwolff0 suggests, one thing you could do is go to the Add/Remove Programs part of the Control Panel and uninstall all of the trial software.

If you follow Ray's tip you will find that some of the well known stuff like Norton AOL are very hard to get rid of.   They remove things from the registry but do not clean the hidden junk.  Delete the folders from program files after they say they are deleted and USE a good Registry cleaner to do their job.

Norton, McAffee and AOL are notorious for these actions.   HP is not far behind.