The path to acquisition can be a tricky thing.
I have a daily regimen. Most of the time I love it but, in true super collecting fashion, sometimes it owns my life. Every day I systematically check different channels at least once. In some cases I check them 50 times a day. Looking at you eBay. I've listed my most common places below in order of success by each channel.
By the way, I highly recommend getting very organized about your channels, tracking successes and setting up a time management strategy to control your cadence on a daily basis.
Private Networking & Community Building (probably the most underrated channel in the hobby)
Secret Sources (in true collecting fashion I can't give everything away!)
Am I missing any sources that you'd recommend?