All About Powder Coating - Contains a list of over 50 powder paint manufacturers and an additional 50 custom coaters with phone and fax numbers, and some websites.
Some information is dated.
Coating Manufacturers Directory - International list of 100 coating manufacturers in a searchable database. Information may be dated. Powder Coating Institute - Lists over 30 manufacturers by category with profiles including address, phone, fax, contact, web link, and brief description. Help build the largest human-edited directory on the web. Wired Digital Inc., a Lycos Network site.