A lot of websites on CNN for large datasets of images talk about starting with the pretrained model for 1.2 million images in 1000 categories available via AlexNet / Imagenet. These sites seem to imply that this dataset is freely available, but I'm having trouble actually getting access to it. For example, I tried going to https://github.com/deep-diver/AlexNet but couldn't get the code in alexnet.ipynb to run. Consider the following code:

for f in data_file.iterdir():
if 'meta' in str(f):
meta = data
elif 'test' in str(f):
test = data
elif 'batch' in str(f.name):
train_dic = merge(train_dic, data)


This seems to imply that there should be some data files which include the text strings 'meta', 'test', and/or 'batch', but I couldn't seem to find those files.

Where is the best place to get access to this dataset--ideally somewhere where there is good documentation as to how to download/use it?

I don't think the original Alexnet is available, but a lot of other models are ready to load from Keras. You may also find a Alexnet version stored as .hdf5 or so online (which you could load with Keras/TF).