FreeDXF is a free .dxf importer for SketchUp.
2012-09-01 Version 0.57
Select the FreeDXF v0.57 option from the Plugins menu.
Most of the options are self-explanatory, with the exception of the "Screen Text" option. Setting Screen Text to "No" will import TEXT entities as geometry (faces and edges.) Selecting "Yes" will import TEXT as SketchUp Text entities - the type that always face the Camera.
Easy Windows Install
For more about how to install plugins for SketchUp, see Thomthom's comprehensive plugin installation guide.