Please feel free to submit updates and corrections. Obviously, I have focused just on resources and links about the Latin language that are in English.
Latinum is unique, as it is an immersion course taught as a living, spoken language. Latin recordings of simple texts, vocabulary, grammatical exercises, etc.
Project Gutenburg online collection of Latin texts, more than 50 free Latin books
Logos Library texts in 100s of languages, including Ancient Greek and Classical and Medieval Latin, plus a conjugator for Greek and Latin verbs, and a quote search.
Fr. Foster doesn't recommend the Collins Gem dictionary, although some beginners find it useful.
Dictionary of Ecclesiastical Latin by Leo F Stelten - for Latin from Scripture, Canon Law, the Liturgy, Vatican II, the early church fathers, and theological terms
A multivolume series with a total immersion, Latin-only approach. The book progresses from easy to more complex Latin, and you obtain the meaning by the context and the pictures and the marginal notes. Learn to read Latin, not just translate Latin. Resources for this method, including a discussion group.
For self-teaching / home-schooling, get Lingua Latina: A College Companion by Jeanne Neumann, which parallels "Famila Romana" on a chapter-by-chapter basis with explanations of all the concepts, study tips, vocab lists, etc.
This series also uses a similar immersion approach to the Latin language. Like Lingua Latina, the stories may be more geared to students than adults and start off rather basic, but soon you will find your grammatical skills naturally growing thanks to this innovative style of learning. Teachers' Corner with many Ecce Romani materials
Peter Jones is also the author of the recommended book Learn Latin - one of the best quick-start introductions to Latin, including answer keys for the self-student.
A deductive text written with the independent learner in mind. Clear and concise gives a solid foundation in classical Latin. The learning curve is a little steep for someone with little prior knowledge of grammar.
A three volume course that tries to keep the grammar lessons short and more time spent reading and immersed in Latin vocabulary than memorizing, designed for the self-learner or a classroom.
A starting reference grammar, a reasonably concise work that describes the essential history, phonology, morphology, syntax and prosody of classical Latin. Not as exhaustive (or overwhelming) as works like Gildersleeve & Lodge or Allen & Greenough (online!)
Course On The Living Latin Language 2nd Edition, by Father Suitbert H. Siedl, O.C.D. - One of the few good audio courses in Latin: one volume with thirteen cassettes.
Forum Romanum DVD a collection of Latin TV Shows, both entertaining and educational
Search for "Latin Primer" at www.ChristianBook.com - it has Video/DVDs of actual classes being taught.
Please support The Amy High Latin Scholarship, a fund established to enable Latin teachers to study in Rome with Fr. Foster.