Research as recent as 2000 shows the structure of the clitoris remains largely unknown:
Entrez-PubMed - Anatomical relationship between urethra and clitoris (J Urol 1998 Jun;159(6):1892-7)
Entrez-PubMed - The suspensory ligament of the clitoris (Clin Anat 2000;13(6):397-403)