If you're interested in more DDoS-style attacks, Cloudflare has an article that goes over the topic as a whole as well as in-depth topics for different common attacks. They also have reports that cover the kinds of DDoS attacks they've seen through their servers. You'll notice they mention SYN floods as one of the attacks they commonly see. Amplification attacks have also risen in popularity, generally speaking, where the request gets amplified by vulnerable DNS/NTP/etc servers.
OWASP is an excellent learning resource as well, and covers many different topics in-depth around web security.