I want to remove a wall. How do I know if it's a load bearing wall?

Start at the lowest point in your house. To begin determining which walls in your house are load-bearing ones, it's best to start at the most basic load-bearing feature of any home - the foundation. If your house has a basement, start here. If not, try to start wherever on the first floor you can locate your house's lower concrete "slab." Once you've reached your house's lowest point, look for walls whose beams go directly into the concrete foundation. Your house's load bearing walls transfer their structural strain into a sturdy concrete foundation, so any walls that interface directly with the foundation should be assumed to be load bearing walls and should not be removed. Additionally, most home's exterior walls are load bearing. You should see this at the foundation level - whether wood, stone, or brick, nearly all exterior walls will extend right into the concrete.

I would go with what Shoshana said. Sounds like she knows how to explain. We actually did the same thing~~expanded our kitchen in to what used to be our dining room, and I love the extra space in our kitchen. Then we build (someone else actually built) cabinets for the end of the kitchen, and we have a ton of space. LOVE it!

Even if the wall is load bearing, have a contractor give you an estimate for taking it down and adding headers. Always get estimates from several contractors.