You've read the first two I'd have recommended to most people, Sparrow. :-) I'd like to recommend Fr. Alexander Schmemann's work next. He's written a number of wonderful books: theological, historical, and devotional. One that inquirers often find helpful and worthwhile is "For the Life of the World". I'll second whoever recommended "The Historical Road of Eastern Orthodoxy", which is an excellent introduction to the history of the Eastern Christian church. I've reread his devotional book, "Great Lent," several times during Great Lent. A bit further into your search, when you're ready for something truly wonderful on many levels, you should read Schmemann's very best work, "The Eucharist." When you're ready for something with real philosophical and intellectual meat, try Christos Yannaras' "The Freedom of Morality." It will stretch your brain, but is IMHO an excellent book for many seekers to read nonetheless.
I'll second Scamandrius's comment on Fr. Vladimir Lossky's "Mystical Theology of the Eastern Church" unless you have a fairly extensive theological background and taste for meaty works with philosophical, as well as theological, depth. It's a *wonderful* book, don't get me wrong, but it's also tough going for most people who are new to Orthodox Christianity.