Adobe officially announced that they will no longer offer older versions of Lightroom and Photoshop (previously you could download old versions):
Please note that going forward, Creative Cloud customers will only have direct download access (from the Creative Cloud Desktop app and Adobe.com) to the two most recent major versions of Creative Cloud desktop applications.
Just a week ago Adobe was "testing" a new $20 per month Adobe Photography Plan by removing the cheaper $9,99 version.
The latest Adobe CC subscription plan rates can be found here (see also this page). A free Lightroom CC trial is available on this page (no credit card required). More information on the different Lightroom versions is available here and here. The different Adobe Creative Cloud options are described here.
For Adobe alternatives check the latest products from Topaz Labs, Skylum and ON1.
Via Petapixel