I asked because burning one gallon of gas creates very near one gallon of water.

Here's an attempt to figure it out. I sometimes make mistakes dealing with a lot of zeros so feel free to check my math.

We've pumped an estimated 135 billion tons of crude oil. The article I read doesn't specify whether it's metric of imperial tons so I went with the later to be on the conservative side.

135 billion x 2000 lbs. = 270 Trillion pounds.

Crude oil density is 7.2 lbs./gallon.
Converting from pounds = 37.5 Trillion gallons.

Using an online calculator- that equals 142 cubic Km's of water.
There's 1,000,000 mm per Km so that's enough water to cover 142 million square Km's. The surface area of the world's oceans is 510 million square Km's.

So humans have raised sea level 0.23 mm.

That's insignificant like ER said, but it's something...

Edit: got to thinking. It's likely some of that ended up as cloud cover and ice