Gentium is the only one that I can think of that is free, but I say your book deserve that you spend some money. From a religious point of view, as much as from a typographic point of view.

It wouldn’t be a big job for a type designer to add a couple of glyphs to a font.

frode frank, what then would you suggest? While I prefer free, if there is a far better font for a decent price, I would be able to save up. Thank you.

Do you need just a roman or as well italics and bold?

Preferably both Roman and Italics. For this project I do not think I need bold type. I should have addressed that in the original post, shouldn't have I?

I'm so used to Linux Libertine having everything that I was gob-stop over its lack of versicle/response glyphs.

Could you tell us a little more about the book and the audience?

And why are you asking for "extensive coverage of ligatures"? Are you relying on the text serif for display work as well?

There are two reasons for my wanting the book to have a free or cheap font: 1) because I do not have the money for a full-fledged Caslon ($135 at one online store and it didn't have the versicle) and 2) because I'd like to be able to make the prayer book available to my parish with as little cost as possible while making it look attractive. At this point in time, I am not planning on making it available on the wider market.

The prayer book, I hope, should contain numerous prayers and devotions from the Roman Catholic faith, mostly in Latin.

My problem with such fonts like Junicode and Palemonas MUFI are that they tend towards the smaller character sizes.

I would like ligatures (especially æ and œ with accute accents) because much of the prayer book will be in Latin and I prefer the more traditional (medieval) orthography, with j, æ and œ. I know the current Unicode charts do not have an œ with an accute accent, which was why I was looking at Palemonas MUFI, as that character is in its Private Use Area coding. I would be willing to save up money for a font if it contained (in addition to the basic characters almost every serif font contains) the versicle, response, œ with acute, æ with acute and the stylistic categories listed in my first post. These are needed because, as a prayer book, it should be dignified in the appearance of its text, and, as a prayer book largely in Ecclesiastical Latin (which does not distinguish between long and short vowels to the extent of Classical Latin), acutes are needed to denote proper pronunciation.

Does this help? Thank you.

I would look at subtle serifs like Cycles, Arno, Minion, perhaps also Arnhem. I suggest you disregard the character set for now and ask the type designer of your chosen face to draw the extra letters.

Thank you very much!

I would consider Andron which has the characteristics you described, but is not free. There is a free roman available, but it has a more limited character support. The Latin Corpus 1 probably covers your needs, with smallcaps, italic and semibold. At € 169 it is reasonably priced for such a good typeface. Also there is a lot of support if you need extra glyphs made.

Cycles is beatiful. It does not have all the characters you need. Sumner Stone has a use-based licensing system, so contact him with your enquiry, and he might be able to help for a friendly price. Cycles 11 or 9 are probably the ones of most interest.

Andron Scriptor Web is a free font providing extensive glyph repertoire for humanist typesetting; Versicle and Responsorio signs included.

http://www.mufi.info/fonts/#Andron

I omitted Andron because the free versions didn’t have italics, but perhaps he doesn’t need them.

If I were you I might have considered the option

ITC Weidemann

Master piece for a prayer book, in my opinion.

Zachary, I don't know how cheap you can go in buying fonts; anyway, if you're after a Transitional serif with old style figures, Baskerville 1757 is a very good and affordable one - roman and italic in Open Type for 79 euro:

http://www.fontshop.com/fonts/downloads/fountain/baskerville_1757_pro/

And there's also an historical lineage, since John Baskerville set a "Book of Common Prayer" in 1771.

There could be many other choices, of course, but this one could fit you well.