Unfortunately those are not the instructions Apple has for opening a library on another drive. Those are for re-assigning where just media (which is not the totality of your library) are stored.
To open the library you need to start iTunes and immediately hold down the option key. When it asks you where the library is located, show it the one on the second drive.
Hopefully re-assigning the media folder location has not made a mess of things.
The secondary drive that contains the iTunes data does not have a "library" item on it. It simply contains two folders, "Desktop" (which is empty) and "iTunes Media" which contains all the folders that make up the iTunes media.
However, there is a "iTunes Library.itl" file in Music/iTunes on the old boot hard drive that was replaced by the SSD. Chosing that library when starting up iTunes with the option key down does seem to fix the problem.
However, this is odd in that now three different drives are involved in this process– the boot SSD, the old boot HD, and the secondary drive that is dedicated to the iTunes media. I wonder if I could just copy the "iTunes.Library.itl" file from the old boot drive to the drive that contains all of the iTunes media?
Read the links below. iTunes uses a somewhat involved structure of files and folders to present what you see as a library. Moving the itl file alone would leave behind other components, but perhaps if you moved the whole iTunes folder to the external it would survive the move. If you are going to do that you might want to consolidate it all to a media folder inside the iTunes folder (see examples in links), making a standard library format and so it becomes more portable in the future.
In general you should not split up the iTunes library unless you really understand how iTunes operates with all these files. I do have mine scattered about, but then I know how it works.
What are the iTunes library files? - http://support.apple.com/kb/HT1660
More on iTunes library files and what they do - http://en.wikipedia.org/wiki/ITunes#Media_management
What are all those iTunes files? - http://www.macworld.com/article/139974/2009/04/itunes_files.html
iTunes 9 [and later]: Understanding iTunes Media Organization - http://support.apple.com/kb/ht3847
Image of iTunes folder structure Dec. 2011 - https://discussions.apple.com/message/16923545
Image of folder structure and explanation of different iTunes versions (turingtest2 post) - https://discussions.apple.com/message/13025536 and https://discussions.apple.com/message/17457605
iTunes: How to move [or copy] your music to a new computer [or another drive] - http://support.apple.com/kb/HT4527 Do not confuse moving your whole folder and library with moving just media files as in: iTunes for Mac: Moving your iTunes Media folder - http://support.apple.com/kb/HT1449
Take a look at my posts Normalize the library and Make a split library portable. There should be enough there to help get your library into shape but I'll happily try to give you specific guidance if it all looks too daunting.
Aha, I see I've been beaten to it.
Message was edited by: turingtest2
Thanks for your reply. I have read over the posts you linked to and I have a much better understanding of how the iTunes file system works.
This is what I did. I copied the iTunes folder from my old boot HD to the secondary HD that is dedicated to iTunes media only. Then when I started iTunes while booted in my SSD drive I held down the option key and chose the iTunes Library.itl file now residing in the iTunes only secondary HD. Now everything seems to work fine. Since I am no longer linking to the iTunes Library.itl file on my old boot HD I believe it is removed from the equation. And in the future it should be easy to link to the self contained iTunes only drive.
Thank you and Limnos for your input. It was essential in straightening things out.