Do you have the grandTheftAuto 3 game on your harddrive?
If so, you can extract all 3300 textures
There’s a whole ‘modding’ community out there with all sorts of tools to export textures / models.
If someone is working on a racer game… (which is surely the case),
then maybe you can use the gta3 cars, the city, and the people.
Anyways, I really like it if people make original artwork, but if you need some good looking (tileable!) grass / wood / bricks / concrete textures, then check it out.