The syntax for sp_add_job has a parameter called @delete_level. If you use this you can set the job to delete itself on completion (wether it is successful or not).
You will need to look at sp_add_job,sp_add_jobstep & sp_start_job. (all in msdb)
Quickest and easiest way to work all this out is to run sql profiler filtered by your username and create a job in enterprise manager. It will give you all the code you need. Job explore the options a little more to make sure your getting everything you want.
Nuke the site from orbit, its the only way to be sure...