Arginine is a nonessential amino acid. It can be manufactured by the human body, and does not need to be obtained directly through the diet.

Arginine plays an important role in cell division, the healing of wounds, removing ammonia from the body, immune function, and the release of hormones (including growth hormone).

Arginine is found in a wide variety of foods, including: dairy products (e.g. cottage cheese, ricotta, milk, yogurt, whey protein drinks), beef, pork (e.g. bacon, ham), poultry (e.g. chicken and turkey light meat), wild game (e.g. pheasant, quail), seafood (e.g. halibut, lobster, salmon, shrimp, snails, tuna in water) as well as vegatrian sources including wheat germ and flour, buckwheat, granola, oatmeal, nuts (coconut, pecans, cashews, walnuts, almonds, Brazil nuts, hazel nuts, pine nuts, peanuts), seeds (pumpkin, sesame, sunflower), chick peas, cooked soybeans, and chocolate.  

References

IUPAC-IUBMB Joint Commission on Biochemical Nomenclature. Nomenclature and Symbolism for Amino Acids and Peptides. Recommendations on Organic & Biochemical Nomenclature, Symbols & Terminology etc. Retrieved on 2007-05-17.