What "exactly" did you purchase? Was it the Acrobat standalone product? Was it the Acrobat Subscription? Or was it the Creative Cloud?
The Standalone installer is located here: http://helpx.adobe.com/acrobat/kb/acrobat-downloads.html
If you purchased the Acrobat subscription then you would sign into Acrobat.com: Acrobat Pro, PDF Pack, Export PDF & More | Acrobat Document Solutions
If you purchased the Creative Cloud then you would sign into that website: https://creative.adobe.com/