Lightroom CC: Cloud storage size of Photography plan is too small (20GB)

20GB is only one of the options. There is a 1TB option with or without Classic and PS. Plus larger sizes.

20 GB does not even cover on photo session :-) :-) :-)
My sessions typically throws 20-30GB :-)

Where do I buy more cloud space and for how much?

I’m transitioning to new LR CC, it is really nice to be able edit my file on cloud from any of my mobile device on the go, but 20GB is no where enough for basic RAW file workflow, the base plan 20GB storage size or 1TB and 20$ per month price are something Adobe need to adjust, or maybe provide better plan options in the future to allow more users transfer to Cloud workflow.

I too was unable to find any option to purchase 1TB of storage. But honestly, I only looked out of curiosity, because I'm not paying $15 a month for storage for my photos. First, Flickr gives me 1TB of free storage. I realize that's for published photos, but it works for me. 

Secondly, I don't want all of that to sync to my phone and ipad, even if I'm only syncing previews. 

I like having the full version on my desktop and LR CC on my iThingies where I can view the folders I've designated as LR mobile photos. That works for me. The new plan does not. And please not that this is not a bitching session, but simply meant to let Adobe Product Managers and hopefully the VPs that make these decisions that some people are not at all interested in this, and the paid storage is too much money, and not an interesting option. This is a good time for Adobe to hear concerns from their users as Adobe contemplates changes in LR moving forward.