Easiest way is to add an inverter, and then you can remote mount the outlets if you need too. You would have to size to inverter to match whatever load you are needing the outlet for, so you may need a "big" inverter depending on what you are wanting to run.
Another thing you might need to consider is if you need a "pure sine wave" inverter, or "modified sine wave". Most, if not all, inverters you find in your local Wal-K-Target Mart will be the modified version. Most things will run just fine off of a "modified" inverter, especially if it has its own transformer.
Another, more expensive, option is to add a generator to your truck. You can get a small one to run off of whatever fuel your truck burns, or it can be belt driven...
Roger