Boosting iron intake

cj4kids

I am consistently noticing this is the macro I just don't manage to eat, despite eating lots of leafy greens (I think that Popeye created a myth there didn't he?).
Where can I get iron from, in a good useable form?
Red meat?
What else?
If you were consistently low in iron (for example last week I was only 22%, the week before 51% - although its possible that nutrition info just wasn't input into some of the foods I have been using, so perhaps I am a little better than I think) would you take a supplement, and does anyone know anything about whether one type is better than another, or if it is one of those supplements best taken in conjunction with something else?