KiCad can create a PCB from a set of Gerber files. It's far from perfect, mostly because a lot of information is simply not present in Gerber files, but it is useful, and much better then nothing. You get about 80% of the PCB in a few minutes of preparation and conversion.
For the rest, you can import "background" graphics both in the Schematic and PCB editors in KiCad. I have reverse engineered some (simple) PCB's from loading photographs into the PCB editor, and I once also used a JPG of a hand drawn schematic as a background picture in KiCad's Schematic editor and put real symbols and wires on top of it. You can scale such pictures to the "actual" size in KiCad, and it is a time saver.