I teach only adults using the Sweet Pipes adult series. They’re very inexpensive ($6.95?) and extremely well written but require, I think, some past music notation experience if you’re going it alone without a teacher. SP2313 for Soprano Book I and SP2318 for Alto Book I will get you started. Those numbers are important as the publisher has a few look-alike sound-alike books for other beginners. No CD or mp3 download available. Many vendors carry these books.
Without a teacher or any musical background, I’ve found there is no better method than Mario Duschenes. Book I has a CD available, which can be a huge help if you’re on your own. (Book I with CD $19.95?) Separate editions for Soprano/Tenor and Alto. I believe all vendors carry Duschenes.
Duschenes Book II is an outstanding book (period!) for all eager-to-improve players that know all their notes. Again, separate editions ($23.95?)
I join in Katia’s recommendation for the aswltd.com commentaries (on every topic.) Long and wordy but authoritative and (as far as I’ve experienced) dead on factually. Don’t be put off by the age of some entries. Little if anything ‘Recorder’ moves very fast except for the Brandenburgs.
— k