When I was in the same boat a clever electrician wired up the old house with some three prong outlets with one hot and two commons. Can't say exactly how he did it, but he made a jumper for each outlet out of single wires he pulled from a coil of three conductor Romex. He charged about $100 to do 6-8 outlets for one hour's time plus the cost of the outlets.
My primary concern was the owner's manuals for my three pronged equipment that stressed "under no circumstances defeat this ground." The electrician explained that the electric company provided the ground back at the power plant so it was better than nothing. His fix did make the ground lamp on the surge strip illuminate so at least the strip seemed happy. The main trick with this fudge job is making sure the hot polarity gets connected the same way in all the outlets. When it's reversed the ground lamp on the strip won't light. Luckily I discovered a reversal or two while the electrician was still on site so he fixed the ones that got flipped. At the time I didn't have a nifty handheld outlet tester so I can't say what it might have shown.
My primary concern was the owner's manuals for my three pronged equipment that stressed "under no circumstances defeat this ground." The electrician explained that the electric company provided the ground back at the power plant so it was better than nothing. His fix did make the ground lamp on the surge strip illuminate so at least the strip seemed happy. The main trick with this fudge job is making sure the hot polarity gets connected the same way in all the outlets. When it's reversed the ground lamp on the strip won't light. Luckily I discovered a reversal or two while the electrician was still on site so he fixed the ones that got flipped. At the time I didn't have a nifty handheld outlet tester so I can't say what it might have shown.