I'm looking into generating addresses outside of Armory using https://github.com/prusnak/addrgen. It requires a master public key which I can't seem find. Does anybody know where I might find it or is Armory not compatible such a system?
AFAIK Electrum is the only client that supports Master Public Keys as of now. Electrum uses a deterministic seed and also have an MPK that can derive bitcoin addresses that belongs to that seed. So people can generate addresses to receive, but can't spend from them; this is called a seedless wallet.