I've been in business for three months. Do I need to file any quarterly tax forms? I don't have any employees (other than myself) and I have not paid myself any wages.
From your description, it sounds like you are operating as a sole proprietor. Because you don't have any employees, you don't have to worry about any of the paperwork employers have to file with the IRS. However, you will have to pay income tax on any profit your business earns. You report your business's profits and losses on Schedule C, which you submit with your personal tax return (Form 1040) in mid April.
In addition to your annual tax return, you may have to file some quarterly paperwork if you are required to pay estimated taxes on your business profits. When you run your own business, you aren't subject to payroll withholding for income tax, Social Security tax, and Medicare contributions. Because the IRS doesn't want to wait a whole year to get its hands on this money, it requires sole proprietors to estimate their tax liability for the year, then pay the IRS quarterly.
If you have a regular job in addition to running your business, you might be able to adjust your withholdings to cover any tax you will owe on business income. If not, you'll have to file quarterly estimated tax returns (using IRS Form 1040-ES and your state's form, if any) and pay these taxes in advance. If you don't pay enough in advance, the IRS can hit you with a bill for interest and painful penalties, come April.