These IP blocks are collected from radb.net using whois, you can try my project getting these.
This is a collection of IP blocks for ppl in China Mainland setting up router.
Google's IP blocks are recorded in TXT(SPF) DNS record, read more here: Google IP Address Ranges
You can also try AS-GOOGLE as an alternative.
No official pages about its ip ranges, TXT(SPF) can be read but fewer than querying from radb
Facebook only provides way querying its crawler IPs: Facebook IP Ranges
Amazon provides a JSON for its IP blocks: Amazon AWS IP Ranges
You can also try AS-AMAZON as an alternative.
Cloudflare provides a JSON for its IP blocks: Cloudflare IP Ranges