Tyco offers various types of PCB connectors for mating PCBs together for e.g., back plane, mid plane, card edge and tab type connectors. These connectors are available as right angle, coplanar or mezzanine interconnects options.

 www.tycoelectronics.com/catalog/connectors/pcb-printed-circuit-board/menu/en/17536?

Information on more products of this type is available at the above link.