I am interested in dabbling in the FS/DFL universe. But, for the life of me, where does one buy these cards? The Nvidia site is always 'out of stock'. Amazon is useless. Ebay has cards at what seem to be highly inflated prices. Everyone else is also 'out of stock'. Any tips are appreciated.
Unfortunately you are in the same boat as a lot of us. You have picked the absolute worst time to try to get into this tech. A combination of a global chip shortage, value in cryptomining and scalpers means that GPUs are currently like gold dust. This also appears to be the case for the 2nd hand GPU market (with old GPUs selling way above their value).
It's a frustrating thing to hear, but my advice is "wait", you either will not be able to buy the GPU you want, or any GPU you do buy will be massively overpriced. Unfortunately this situation is predicted to continue throughout 2021.
If you have a friend who can lend you a GPU, then that's the way I would go right now. Alternatively I would be looking to buy cloud compute (e.g. GCP: viewtopic.php?f=23&t=357 )
My word is final