Location & Description (Novel & Film)
The only "Canon" photo known is depicted in the InGen Field Guide, stating that InGen was based in Palo Alto, with another California corporate location in San Diego. The photo appears to be accurate to its novel description; a large corporate & laboratory building, approx. 200,000 sq. ft. in area. There are also several trees in front of the Headquarters.
Location & Description (Comics)
Another version of the InGen Headquarters appears in the Topps comics, but it differs slightly from its counterpart; it seems to have the "InGen" logo with an enlarged "N" bottem spread throughout the top of the building, with the main lobby sharing the logo as well.
Staff & Personel
Parker is also considered the main receptionist as stated in Jurassic Park The Game.