The employer is permitted to not provide a W-2 only if wages were under $600 and there was no withholding for income tax, Social Security tax and Medicare tax. It's extremely unusual for the requirements permitting the employer to avoid issuing a W-2 to be satisfied since most employees are subject to Social Security and Medicare tax withholding.
If you are instead self-employed and the company is your client, it's your responsibility to report self-employment income even if the client does not provide you with a Form 1099-MISC. Self-employment income is reported in the business section of TurboTax as described y VolvoGirl, not as Other income.
