AutoCad is great but hopless when it comes to import other formats. I needed to vectorize a metal band logo for a project. Long story short:
1. Open the bitmap image in Inkscape (open source vector editor) and goto path – trace bitmap.
2. Select traces and do object – ungroup
3. Path Break Apart
4. Copy the traced vector path with ctrl+c
5. Open openOffice Draw and paste with ctrl+v. You have to copy this way instead of saving to a common format to avoid great quality loss.
6. Export to Windows Metafile.
7. In AutoCad goto Insert – Metafile. Voila!