this blood's not my type

I have recently realized (again) that I have no idea what my blood type is. And for a girl who has had gobs and gads of medical testing in the past couple of years, and is startlingly in tune with her body, this is a startling revelation.

This isn't a case of knowing at one point and then forgetting.  I'm really not sure I've ever known my blood type.

This is an important thing to be aware of, it seems.  I've had the first aid training and CPR certification and what not, thank you ARC, so I know that I really ought to know this.

So I'm wondering how I can go about finding out.  I've had a lot of blood work done in recent years - does anyone know if testing for type is a part of 'blood work' or if it needs to be specifically requested?