Make an extruded circle along a path into a solid object I'm trying my hand at 3d printing with blender. Right now I want to create an object that has a 3d curve - so it's essentially a horizontally placed cylinder curved around the Y axis on the whole object, and then curved along the Z axis for the last third of the object. I've found I can model exactly what I want by creating a curved path, then extruding a circle along the path. 

However, I haven't found a way to 'apply' this transform so that my 2 objects become one editable object where I can close off the faces and select and edit nodes. Can anyone tell me of a way to do this? I also tried having a straight cylinder object and applying the curve modifier, but found that only worked along one axis, and attempting to use 2 curve modifiers on the same object gave funny results.
You can join two meshes by using Ctrl+J, however make sure they are both a mesh before attempting this. As Reactive said, you can convert a curve into a mesh using Alt+C > Mesh from Curve/Meta/Surf/Text. If it is using a modifier, simply press the Apply button before joining the meshes.