Need help buying a used car.?

I have never purchased a car before so this is my first time. I also reside in Northern VA, USA (Fairfax County) and i have very limited knowledge about car buying, process and formalities that need to be done b4 and after buying the car. Is there any organization/company or good consultants who can sit with me and discuss my budget and pricing and then give me some best deals. Also provide step by step guidance as to how i should proceed with car financing, titling and registration. Things i need to do before and after buying a car. I would need all these guidance. Are there any consultants available in Northern VA area who can personalize my needs and offer some best deals for used cars ? I would appreciate all your answers.