It appears that the average consumption of toilet paper in Germany is 46 rolls per year. (Source in German.)

Nic has measured a roll of toilet paper and determines they are approximately 10 cm wide. And he concludes:

If you put the 46 rolls next to each other, that would make a row of about 5 meters. Now, there are about 80.000.000 inhabitants of Germany […], that makes 400.000.000 meters = 400.000 kilometers of toilet paper per annum. That is 10 times round the world.

And that is just measuring the width of the rolls – not their length. :-) (Superficial research shows that a roll of toilet paper is between 20 and 40 meters, depending on make and paper.)

(More interesting statistics at Toilet paper encyclopedia.)