I have unilateral tinnitus from about 4 months, feel a little unsteady sometimes. No hearing loss. Worried abt Acoustic neuroma, is it common?

No, but..... Acoustic neuroma isn't common but it happens and it is serious. Your symptoms are worrisome. In any case you need to see a doctor about your symptoms. You can start with a primary care physician who will refer you to the appropriate specialist for further evaluation. Please don't procrastinate!