My partner and I are looking to set up a business that will require
the design of elaborate sets or scenes that will comparable in quality
to that in Broadway musicals or even movie sets.
Does anyone know where I can find a list of set designers/companies to
find out more information and get quotes?  We are located on Long
Island so preferably something that is on the East Coast would be
good.  Thanks!

Hi Browntaylor,

The link Pink gave you is a derivative of the Open Directory page by
the same name (Arts: Performing Arts: Theatre: Stagecraft: Set Design:
Designers).  This one is probably updated quarterly - to get the most
up to date listing try this link:
http://dmoz.org/Arts/Performing_Arts/Theatre/Stagecraft/Set_Design/Designers/

You might actually find some good people among the stagecraft crowd -
who aren't necessarily specifically set designers.  The DMOZ category
for that is Business: Arts and Entertainment: Tools and Equipment:
Scenic (http://dmoz.org/Business/Arts_and_Entertainment/Tools_and_Equipment/Scenic/).
This category includes groups and studios, whereas the other category
is for specific set designers (not groups).

Out of these two categories, many of the listings are in New York
(being the theater capitol of the East Coast, if not of the US).  The
following specifically mention New York in their description:

Oliphant Studios
http://www.ostudio.com/

Cwalina, Kevin 
http://www.geocities.com/broadway/alley/1792/

Creech, John
http://www.johncreechdesignandproduction.com/

Aronow, Scott
http://www.scottportfolio.com 

Schweikardt, Michael
http://www.msportfolio.com

Zieglerova, Klara
http://www.klarazieglerova.com/

Garcia, Regina
http://www.garciaportfolio.com

Pollard, John
http://www.jpollard.com

I hope one of these does the trick!  Let me know if I can help you further -

Librariankt

The Google Directory has a category that might be useful:

http://directory.google.com/Top/Arts/Performing_Arts/Theatre/Stagecraft/Set_Design/Designers/

If you'd like a Researcher to investigate local options, you may want
to increase your price considerably. It is not likely that anyone will
spend more than five or ten minutes on your question in order to earn
$1.50 (the Researcher's share of your current fee).

Actually, this comment works just fine!  Thank you, pinkfreud.

Hello browntaylor~

Most Broadway-calibur theatrical scenic designers belong to United
Scenic Artists (U.S.A.). The New York local can be reached at:

29 West 38th St.
New York, NY 10018
212-581-0300
Fax: 212-977-2011 

I would advise calling the local, explaining your situation, and then
ask how you can post a notice, seeking designers. They should be happy
to help you. This will be the most effective way to get a nice
selection of designers to choose from.

Kriswrite