iptables-fu

I've had a love hate relationship with iptables. I love the control it offers but, am quite confounded by all the low-level networking concepts at play. Today, I had to do some simple stuff, like blocking pings and block ssh from a particular IP. Here is my humble attempt at both

# reject all ping requests
iptables -A INPUT -p icmp -j REJECT
# drop all ssh (tcp:22) requests from 10.0.0.37
# DROP means that whoever is trying to connect from 37 will not get a connection refused...devious >(
iptables -A INPUT -p tcp --sport 22 -s 10.0.0.37 -j DROP