The following are services I personally use and recommend.
PBN Hosting
Domain Scrapers/Auction Domain Providers:
Kalin: https://seo.domains/
Max/Nargil: His BHW Thread
Patrick: https://www.serpchampion.com/
Sumit: http://www.dominatingpbns.com/
TB Solutions: https://www.tbsolutions.info/
Auction Sites
Dropcatch: https://www.dropcatch.com/
Namejet: http://www.namejet.com/
Godaddy: https://auctions.godaddy.com/
Pheenix: https://www.pheenix.com/