you can but it at the supermarket, Kikkoman just came out with one and its pretty good.
You can also make it, its little more than lemon and soysauce with a little sweetner in it.
- 1/2 cup low-sodium soy sauce
- 1/4 cup fresh orange juice $ Click to see savings
- 2 tablespoons fresh lemon juice
- 1 tablespoon water
- 1 tablespoon mirin (sweet rice wine)
- 1/8 teaspoon crushed red pepper