Originally Posted by hartkem
I want to direct bury some 12-2 feeder wire to a small garden shed...
You don't need pipe. The GP circuit for your shed can be achieved with an underground romex type wire (called "UF"). You'll still have to make a narrow trench though.
Is it OK to tap into the outside electrical receptical to supply power to my shed?
Depends on how that receptacle is set up and where it gets power from.
Ideally... it is part of a 20A GFI protected circuit. If so, you're golden.
If not, then you should plan to go to an existing 20A GFI protected circuit...
or back to the panel and start a new one.