2 times over the past few days I have had to ask a friend to lookup the IP for www.satannet.com and manually add it to my hosts file. Has anyone else had this problem or is my nameserver just screwed? (I haven't had this issue with any other sites)

What OS are you running?

FreeBSD on my main desktop, but i've had the same problem from various machines and from the windows boxes at uni.

Do they all use the same DNS? Or different ones?
Maybe you have got a christian provider and it don't resolves satannet.

At home I use my own nameserver which talks directly to the root nameservers. Every few days it stops resolving satannet. At university, they use servers provided by janet (www.ja.net).

... strange - i never had problems like this - maybe try out these ones:
213.178.66.111
213.178.66.112

Seems to work
thanks