Inspired by a paper with all it's citations linked to Google Scholar, I had another look at Google's service. It's useful if you can find the item you are looking for, and if the item is cross-referenced - Google figured out its citations, and other items that cited it.
I added Google Scholar links to the Gesamtausgabe App's (the GAApp?) Paper and Book details pages. In the case of papers, the URL linked to Google has the title (URL encoded; e.g., "Logic: The Question of Truth" => "Logic&3a+The+Question+of+Truth") and the Author's name in the form Google likes it (Initials and last name; e.g., "Andrew J. Mitchell" => "AJ+Mitchell"). I had to right a function to convert names to that format. With Books, if there's an author, the URL is the same as papers. If the book doesn't have an author, but has an editor, then URL uses the editor as the author. If the book has a translator but no author, then URL uses "M Heidegger" as the author.
The links appear to return pretty good results. Google Scholar either finds an exact match if its there, or reports it can't find it, without returning a bunch of unrelated results. Google should support searches with books' ISBNs t improve results when looking up books.
I'm considering also linking People in the GAApp to Google Scholar, and also individual Texts - most of the Texts in Wegmarken appear Google as individual citations.
I have not pushed this latest version of the GAApp to the cloud yet. It'll be in version 1.3.
[Update 4/16/15: I just discovered my simple author's name algorithm doesn't work with "Miguel de Beistegui" => "Md+Beistegui", no matches for his "The New Heidegger" on Google Scholar. The search has to be specifically for "M+de+Beistegui" to return the book. Other of his books require searching for specifically either "M+Beistegui" or "Md+Beistegui". Sheesh. Come on Google. Apply some intelligence, artificial or otherwise, and link all the variations to the same person, and have a query with any variation return all of a person's citations.]
