Other than the Omega materials supplied by Gerber, I haven't heard of one. Various Gerber distributors provide training in different forms and Bob Gilliland, who is a member here, does seminars. Lots of stuff also at most sign expos.
The Gerber Edge book
By Dale Dunnihoo
(it was $99... not sure if it still is)
Here's an outline Theresa sent me when I inquired about it a while back.
Dale Dunnihoo began writing Imagination’s Edge when he installed the Gerber EDGE in his sign shop in 1993. The technology of color thermal transfer was new to the sign industry so he began writing journals to document everything that he and his designers were learning. This book is the result of those findings.
Maximizing the EDGE begins with establishing a technical foundation based on the strengths and limitations of the printer itself. You are not able to view any of the available halftones on your monitor so it is essential that you have actual Gerber EDGE output to determine exact halftone selections and LPI settings. Likewise, the colors that you see on your monitor are only representations of actual EDGE color so it is also essential that you have printed color test files. Other variables such as different methods of image acquisition, color space selection, file type selection, file size, resolution and intended viewing distance all influence the look of the printed image. And even the foils that are run through the EDGE influence final color. Many shops use all of the Gerber foil lines (Super CMYK and ColorSet, spot, etc.) and third party foils are becoming common in many shops. There is a series of halftone test files, color test files and image quality test files that will help you choose the best settings based on all of these variables. And there is original artwork images on the CD that can be printed out and used for sales displays and portfolios.
Other sections contain information that relate not only to the EDGE but to digital imaging in general. - Photoshop techniques and special FX software, for example. As markets grow and other printers find their way into sign shop production departments, this information will benefit the operators of these printers as well. The topics of aesthetics and sales are covered as are suggestions on how to define these unique EDGE products with a price that reflects their value.
The GERBER EDGE Book Outline:
THE DIGITAL STUDIO
Computer station setup
Production department setup
Basic file setup
Raster to vector scanning techniques
Basic color scanning techniques
Sign design and layout
Graphic elements and style modifiers
Image quality test files
Image quality test files
WORKING WITH BITMAPS
You're right that there is a market - both from the number of installs worldwide and from the perspective that everything from designing, to production, to marketing for EDGE output is rather unique on many levels (just as the machine's capabilities are unique). I think it fair to add that many EDGE owners don't even approach using their machine to its fullest potential...and would probably love a comprehensive guide of some kind.
If you're serious about persuing this, I might be able to help. Feel free to drop me a line. I'm anything but a regular poster on Signs101 - so if you aren't familiar with my "credentials" please ask. I will warn you, however, that I'm not in a position to take on any new projects for several months.