If we don't have CUDA enabled GPUS

I was told that for those of us without access to CUDA enabled GPUs there was a web site, where we could log on and compile and test code.

Does anyone know the URL?

You would be referring to the online self paced training labs. You can find links to these labs on the how to get started with CUDA page: https://developer.nvidia.com/how-to-cuda-c-cpp

Labs are available for languages other than C.
Good Luck.