You could use either a tax attorney, Certified Public Account (CPA), a professional tax preparer, or you could file the returns yourself. It all depends upon your comfort level and finding the person - be it you or a professional - that has the requisite skills and knowledge to complete the tax return for the price you want to pay. In your situation, you would probably not need a tax attorney. Tax attorney's are useful for tax planning for organization and transaction purposes, but are usually not necessary for the preparing of a tax return. Depending upon the size of your business and its future growth, you might want to start working with a CPA or tax preparer. Then, as the business becomes more complicated, you will want to talk to a tax attorney or business attorney about whether or not you need to re-organize your business (i.e. LLC or incorporate, etc.).
You might also want to consider using an enrolled agent - in fact, in my opinion that would be far preferable to using "just" a licensed tax preparer since enrolled agents are required to successfully complete a rather difficult test in order to use the designation "enrolled agent".
You need a certified public accountant. Tax lawyers do tax planning; the good ones do not help people fill out 1040s. Tax preparers (those who are not CPAs) are not as good as CPAs are at helping business people. A good CPA knows when to send someone to a tax lawyer.