If you crunch the actual numbers (I did this once), iron absorption from plant and animal sources can be roughly equivalent--providing you do things to maximize the absorption of plant iron. (FYI, much of heme iron, the iron found in meat, is also not absorbed). The most important thing is to combine iron sources with sources of vitamin C, which significantly increases iron absorption. You should also avoid eating foods high in calcium with food high in iron, because the two bind, so the absorption of each is inhibited (this is why spinach isn't a great source of iron, for example).
So some examples:
*oatmeal w/ blackstrap molasses and a glass of orange juice
*chickpeas or beans w/ quinoa and red bell pepper, etc.
*toasted pumpkin seeds on a salad that contains mandarin oranges or as a snack with strawberries or another vitamin-C rich fruit
This page has a list of plant foods high in iron.
http://www.vrg.org/nutrition/iron.htm