Order from a reputable source.. whether it's an individual or a business. Obviously, ordering online could mean a lot... I assume you don't mean pizza. Whether it's fish or dry goods, the same applies... feedback/reputation is very important. If it's fish, make sure you're not paying ridiculous shipping fees, as it's only about $12 for most orders using priority mail (I guess the same would apply for dry goods, though it's not usually as big of an issue).