I'm in my 40's and just completed a Masters degree in IT Management from Brandeis University, I already had a Bachelors in both Business and Computer Science. The degree spanned two employers, both of which offered employee education reimbursement.
I guess you could say that I am now three degrees above zero... ; - )
A Masters degree is 10 courses and can be completed in 3 to 5 years when going part-time. For most Master's programs, if not all, you first need a Bachelors degree. Some educational institutions will recognize work experience as an equivalent.
It sounds like you have not completed a Bachelors degree. A Bachelors degree takes 120 credit hours or 30 per year over 4 years. It's a lot of work and time which is why most students go full time. Basically, you wouldn't be completed in time for it to help your career.
The first step to get a Masters degree, assuming you are working full time and are not a contractor, is to determine if your employer has an education reimbursement program, what their limits are per year, and what you need to do to apply. If they do, you next need to research the type of Masters degree you want and the schools. Narrow down the schools to your top 5 and begin calling their Admissions department to determine if you can use your work experience and what, if any, additional courses you will need to take. While doing this, talk to your manager and let him/her know that you are interested in advancing your career by taking a Masters degree. Go into how it will prepare you to take on a greater leadership role, in project management and as team lead. Once you have all of the information about the school, put it together in a package with your employer education application and begin the employer approval process. Once approved at work, you then need to apply to the school and get accepted. The rest is just a lot of hard work...
David