I don't know if a site exists (and if fact doubt it - despite the good work being done in many fields with primary sources, I have yet to see much good online secondary work - that isn't just the online version of a print journal).
That said, the only book that I've seen which discusses what you're talking about is called Hymn of Entry, by Abbot Vasilios of the Iviron monastery. Though the book is written to be an explanation of why the Holy Mountain was opposed to the EP-Vatican ecumenism of the 1970s, it's really much more than that because he puts it into a theological framework. And this is "real" (for lack of a better word) theology - it's not philosophy or history, it's a written articulation of the life and experience of the Church in several areas, and within it
Be advised: it's not easy, light reading. I honestly think that the average layman would have to have been attending just about every service at Church (Vespers/Orthros/Liturgy+Lent, Holy Week, etc.) consistently for at least several years in order to be able to make sense of it.
[I suppose the question will inevitably arise: why am I still in union with Rome if I think so highly of Abbot Vasilios' books? Short answer, I think his characterization of Rome - even though it's perfectly in line with what he'd learn in France in the 1960s, and basically in line with the Catholic answers crowd - is inaccurate; and that Rome's nature - understood in its own terms - are essentially in line with what he writes. That is, as much as I admire his work and that of Abbot Aemilianos and of other writers, I don't see anything that's outside what I've seen with Rome. But that's the subject of a totally different thread. If it comes, I'll participate. If not, I'll leave it at that.]