Vocal techniques - nice page of "techniques, ideas, and inspirations to help us all sing better" compiled by Mike Monkowski from Newyorkers Chorus
Society Music Catalog
Searchable BHS Music Catalog
JOE JOHNSON (House of Joseph)
Music Educators Resources
Free 'n Easy
Music Premiere Series
Heritage of Harmony Songbook
Barbershop Arrangers
Learning tracks
Classic Tags For Men (w/learning tracks) PDF
Sheet Music Plus
Steve Jamison's gems:
De-emphasized syllables
Tension & Release
Diphthongs
Individual Resonance
Vocal frye exercises by Mark Gordon. There are other great vocal exercise on his YouTube site
SO YOU WANT TO SING IN A QUARTET (by Jim Milner, August 1998)
PM WARMUP EXERCISES - 1, 2, 3, 4, 5, 6, 7, 8, 9, 10 =
11, 12, 13, 14, 15, 16, 17, 18, 19, 20
BURT SZABO'S FIVE-CHORD VOCAL WARM-UP
LEARNING A SONG BY JAY GIALLOMBARDO
Debra Lynn, one the best vocal coaches and specifically for barbershop singing. She wrote a book and an article in Harmonizer about singing like Italians. Here's the link to her book "The Bel Canto Buzz: Beautiful singing made simple". One of the reviews is mine. She is my vocal coach and I love every minute of the Skype sessions. Contact her by email or Twitter
Tony De Rosa is a great coach. You have to join the Heralds of Harmony or the choruses he coaches
I heard on Gold Medal Moments podcasts Toby Shaver speaks highly of his vocal coach Ben Harding, the lead of After Hours quartet. His company is called Vision Vocal Coaching, and here's his email