The list below is current as of July 2017. These companies are ever-changing with the closure or merging of businesses. Hopefully, you will be able to find those your are looking for.

Ann Original Molds: http://www.annoriginalmold.com/
Anthony's of Solvang: http://www.anthonysdesigns.net/
Cindy's Molds: http://www.cindysceramicsandmolds.com/... (Atlantic, Byron, Ceramic Emporium, Ceramichrome, Cindy's, Crest, Duncan, Glenview, Marco, Mayco, MOM, Rocking Horse, Weaver, Yozie)
Clay Magic: http://www.claymagicinc.com/ (Clay Magic, TL)
Coloramics: http://www.maycocolors.com/ (Coloramics, Cardinal Designs)
Country House Molds: http://www.chmoldco.com/ (Yozie)
Creative Paradise: http://www.creativeparadise.biz/ (Creative Paradise, Kimple, TL)
DAC Molds: NO WEBSITE 503.658.2453 (Alberta, Atlantic, DAC, Georgie's)
E&T Industries: http://www.daddymolds.com/ (Daddy's, Dragon, Favor Rite, New England Old Town)
Gateway Molds: NO WEBSITE 386.288.7609 https://www.facebook.com/sherrys.ce...
Gem/ Trenton Molds: WEBSITE IS UP AND DOWN http://www.gemceramic.com/index.htm... 717.336.2798 (Atlantic, Nancy's, Trenton)
GRD Molds: NO WEBSITE, Facebook entries only https://www.facebook.com/media/set/...
HK Enterprises: http://www.hkenterprises.org/ (Air Capitol, Anchor, Atlantic, Bil Mar, Brush Country, Bug, Byron, Ceramichrome, CJ's, Cramer, C'rmic, Crest, FA, Gemini, Glenview, HK, John's, Mayco, McRon, Mike's, MOM, Morning Star, Mountainside, Nancy, Ocean State, PCM, Provincial, Rocking Horse, Santmire, Shade Tree, Sunrise, Tesoro, TJ's, Vicki, Western, Yozie)
Holland Molds: http://www.hollandmolds.com/ (Ceramichrome, Gare, Holland, Kentucky, Norwood, Ocean State, Reward)
Kentucky Pottery/ Doc Holliday Colors: http://dochollidaycolors.com/
Macky/ Oregon Ceramic Supply: http://www.mackymolds.com/ (Alberta, Arnels, Atlantic, Bil-Mar, Boothe, Brush Country, Byron, Castle, Catskill, Ceramic Emporium, Ceramichrome Crest, Davis, Fairy Princess, Holland, Kansas, Kelly, K.C., Molds, Kimple, Kinzie, Macky, McRon, Mike's, Nancy, New Horizons, Oasis, Ocean State, Power Design, Provincial, Shade Tree, Sittre, Tampa Bay, Tesoro, TL, Western, Vicki, Yozie, etc.)
Magnolia: http://www.magnoliamolds.net/ (Jones, Magnolia, Pine Tree)
Master Sargent: http://www.mastersargentmolds.com/
NBE: http://www.nbemolds.com/ (Casco, NBE, etc.)
Petro Mold Company: http://www.petromolds.com/
Pontepinto: http://www.pontepinto.com/
Riverview: http://www.Riverviewmolds.com/ (Riverview, Ross)
Shiloh: http://www.ceramicshop.com/ (Alberta, Byron, Heinz, Hershey, Nowell, Provincial, Shiloh, Victory)
Skyline: http://www.skylinemolds.com/ OR http://www.ceramic-molds.com/ (Alberta, BJ's, Clear Creek, Cloud Mountain, Cole, Crest, D&R, Jamar Mallory, Jasper, Jay-Kay, Majesty, Shirley, Skyline, TM, Yozie)
Starlite: http://www.starlitemolds.com/ (Alberta, Clay Magic, Cole, Doc Holliday, Dona, Duncan, Heinz, Jamar Mallory, Madeinfire, PK, Scioto, Starlite, Suncrest, TL)
Waer: http://www.moldsbywaer.com/ (an NBE subsidiary)

Foreign Mold Companies:
Alberta Deutschesland: http://gipsformen.de/Kataloge/Home1... (All former Alberta sublines).

Porcelain Mold Companies:
Bill Mac: http://www.bilmacdollmolds.net/
Faces Past: http://www.facespast.com/
Mystic: http://www.mysticmolds.com/