Have you found yourself waiting hopefully for your favorite classical or opera LP recordings to reappear on CDs? Or, worse, have you lately discovered that the CD you planned to collect entered and exited the catalog before you knew about it?

Well, you might be surprised to find that the title you crave is available, though not in retail stores. New Jersey-based, family-owned Musical Heritage Society has signed licensing agreements with several of the largest classical labels and now offers many acclaimed recordings from Philips, Sony, Deutsche Grammophon, EMI-Angel, BMG-RCA and London, to name a few. (Even though MHS entered the retail market with its own MusicMasters label, the company''s subscriber-only catalog continues as the largest mail-order source for classical music, as it has since the 1960s.)

Originally released in London, you will find Mahler''s Das Lied von der Erde with James King, Dietrich Fischer-Dieskau and the Vienna Philharmonic under Leonard Bernstein and the 1977 world premiere recording of Leoni''s exotic 1905 verismo opera L''Oracolo starring Joan Sutherland and Tito Gobbi. From EMI-Angel, Strauss'' Ariadne auf Naxos in the celebrated 1969 recording under Rudolf Kempe and starring Gundula Janowitz, Teresa Zylis-Gara, King, Theo Adam and Hermann Prey; Mendelssohn''s oratorio Paulus with Fischer-Dieskau and conductor Rafael Frhbeck de Burgos; the complete sacred works of Schubert on seven CDs with an all-star cast and the Bavarian Radio Orchestra conducted by Wolfgang Sawallisch; and Rafael Kubelik''s acclaimed 1971 recording of Wagner''s Lohengrin with King, Janowitz, Thomas Stewart and Gwyneth Jones.

The Deutsche Grammophon catalog is generously represented, and includes: Mahler''s Des Knaben Wunderhorn with Lucia Popp, Andreas Schmidt and the Concertgebouw under Leonard Bernstein; Mahler''s Symphony 4 with Edith Mathis, the Berlin Philharmonic and Herbert von Karajan; Brahms'' four symphonies, Academic Festival and Tragic overtures, Haydn Variations plus four choral/orchestral works with the Berlin Philharmonic, led by Claudio Abbado; the complete sonatas for violin and piano by Beethoven with Gidon Kremer and Martha Argerich; and the six Bartok string quartets with the Tokyo Quartet. On DG Archiv, find Handel''s oratorio Sampson with Alexander Young, Martina Arroyo, Thomas Stewart, Ezio Flagello and Karl Richter conducting; the complete harpsichord concertos of JS Bach with Trevor Pinnock and The English Concert; and David Munrow''s Early Music Concert release Music of the Gothic Era.

From

Philips, again naming only a few, the complete Concertgebouw recordings by George Szell (including music of Schubert, Mendelssohn, Mozart, Beethoven and my own favorite recording of Sibelius'' Symphony 2); and Janet Baker''s incredible performance in Handel''s opera Ariodante with Edith Mathis, Samuel Ramey and the English Chamber Orchestra conducted by Raymond Leppard.

The MHS catalog includes CDs from BIS, Hyperion, Denon, Nimbus/Prima Voce, Mercury, MusicMasters (of course), classical and opera VHS videos and a sizeable jazz collection. MHS operates like a record club with a featured CD (described a new release brochure every three weeks) which will be sent unless a notice is received by return mail. CD prices fall generally between full retail and big-volume discounters. While a few of these specific titles may still be obtained in their retail releases, they are not otherwise currently available. To find out more, write to MHS, 1710 Highway 35, Oakhurst, NJ 07755; phone (732) 531-7003.

Last Week''s Quiz: What is the overriding principal pursued by Wagner in his greatest works >(Der fliegende H”llander, Lohengrin, Der Ring des Nibelungen, Tannh„user, Die Meistersinger, Tristan and Isolde, Parisfal)? Answer: Redemption though love.

This Week''s Quiz:

What 20th-century composer in 1917 wrote a cantata whose name and subject are the Greek goddess Demeter?

Classical Calendar

UCSC Dance

Friday/Saturday, 8pm; Sunday, 3pm. Silva Martins and student dancers appear in Spirited Moves, new works by choreographers Mel Wong, Remy Charlip. Mainstage Theater, UC Santa Cruz. $9. 459-2159.

An Evening of Opera at UCSC

Friday/Saturday, 8pm. Music and Theater Arts Depts. present "Berlin to Broadway with Kurt Weill," directed by Patrice Maginnis, Michael McGushin. Music Center Recital Hall, UC Santa Cruz. $8/general, $5/seniors, $3/students. Reservations, 459-2159.

Northminster Concert Series

Saturday, 7:30pm. San Jose Choral Project performs Gorecki, Durufl‚, Tavener and others. Northminster Church, 315 E. Alvin Dr., Salinas. Free; donations accepted. 449-2717.