Pine
Pine comes in several varieties, including Ponderosa, Sugar, White, and Yellow, and all of them make great furniture. In some areas of the country (especially southwest United States), pine is the wood to use. Pine is very easy to work with and, because most varieties are relatively soft, it lends itself to carving.
Pine is commonly used in furniture because it's easy to shape and stain.
Pine generally takes stain very well (as long as you seal the wood first), although Ponderosa pine tends to ooze sap, so be careful when using this stuff. Pine is available from most home centers, but it's often of a lesser grade than what you can find at a decent lumberyard.