This is an exercise to find an autographed manuscript. I chose Symphonie fantastique by Berlioz because it is one of my favorite pieces of music.
I started by going to Oxford Music Online (contains New Grove Dictionary of Music).
I searched for "berlioz" and selected the second result because it was his New Grove Dictionary entry (which is what you want). I realize that on this screen there is no way to obviously tell that. That is a fault of this search result page. In the next screenshot, notice how in the top left under "Oxford Music Online" "Grove Music Online" appeared; this indicated that I was looking at the New Grove Dictionary entry.
I was looking for the "Works" section, which is usually towards the end, so I scrolled down.
I found a catalogue of his works (Catalogue of the works of Hentor Berlioz) and noted the abbreviation in brackets ([H]), which I will need in the next steps (this abbreviation is not always present, though).
I scrolled down to the category of work I was looking for (symphony) and clicked on the "View large" button.
I found the particular piece I was looking for (Symphonie fantastique) and noted the numbers to the right, which are where I will find the piece in the books that correspond to the letters (this is why I needed the H from earlier).
I searched the UMD catalog for the Berlioz catalogue and found it. I retrieved it from Reference in MSPAL and turned to entry 48.
Under "Sources," I found the autograph score. The abbreviation "F-Pc" is shorthand for its location in the world. I had to go back to Oxford Music Online to find a listing of these abbreviations.
I clicked "Tools and Resources" along the top of the screen, then "General Abbreviations." "Library Sigla" is the category for this abbreviation.
The F was for France, the P for Paris, and C for Conservatoire (in this case). Now I needed to find their website and catalog to see if it was really there or not.
I Googled "paris conservatoire archives" and clicked on the first result because it looked like a good place to start. Note: from here on out, I sometimes had to use Google Translate on these webpages.
This is the website for the National Library of France, in particular their Music Department (they apparently have the "heritage collections" of the Conservatoire). They appear to have autograph manuscripts by Berlioz, but do they have the piece I am looking for?
To find out, in the search bar I entered "symphonie fantastique autograph manuscripts berlioz." Alternatively, I could/should have searched for the title of the piece plus the shelf number (ms 1188) and found it that way.
The first result looked like what I was after, but clicking it just took me back to this page, so I instead clicked the link that looked like it would take me to all of the results.
I was right; this appeared to be the catalog. I scrolled down until I found what looked like the score (searching for the title and shelf number would have made this the first result).
I finally found the autographed manuscript.