Methods and apparatus for forming devices using nanotubes. In one embodiment, an apparatus for depositing nanotubes onto a workpiece comprises a vessel configured to contain a deposition fluid having a plurality of nanotubes including first nanotubes having a first characteristic and second nanotubes having a second characteristic. The apparatus further includes a sorting unit in the vessel configured to selectively isolate or otherwise sort the first nanotubes from the second nanotubes, and a field unit in the vessel configured to attach the first nanotubes to the workpiece. For example, the field unit can attach the first nanotubes to the workpiece such that the first nanotubes are at least generally parallel to each other and in a desired orientation relative to the workpiece.