Starting solids by introducing rice cereal is the standard - but this doesn't mean you can't start with other foods. Rice cereal is easy to digest and has a very low risk of causing an allergic reaction. Other grains, like oats or wheat, contain gluten that can be hard on a baby's delicate system.
If you are looking to buy a box of instant organic brown rice cereal look for trusted brands like Earth's Best and Healthy Times. Gerber offers organic brown rice cereal and other organic baby food under it's label Gerber Organics. Always read the ingredients on the package to be sure additional ingredients are left out.
Prepare a small amount of rice cereal with enough breastmilk or formula to make a runny consistency. Use a small rubber-coated spoon for your baby's first feeding. Don't worry if not much food makes it to his tummy. This is mostly practice.
You can even make your own organic brown rice cereal. Grind 1/4 cup organic brown rice in a coffee grinder until it is a powder. Add the rice powder to 1 cup boiling water and cook, stirring, for 10 minutes. Add breastmilk or formula to adjust the consistency.