@SusieQ100: The grafton series is one example where calibre's title sort generation falls down. In particular, the book 'A is for Alibi' ends up sorted under 'is', because calibre thinks that the book's title is similar to 'A Perfect Nightmare', which should sort under 'P'. In other words, calibre is treating the 'A' is an article, not a full-blown word in the title.
Before I go in, is this your problem? If jackie_w's suggestion fixes it, then we don't need to get 'technical'.
OK, since you are still reading, there are three possibilities to consider. Reacting to these possibilities include changing 'tweaks', something you might find 'technical'. Many people have succeeded. If something isn't clear to you, ask.
The first possibility: you don't want calibre to do leading article detection, ever. In other words, you want both 'A Perfect Nightmare' to sort under 'A' and 'The Anarchist' to sort under 'T'. If this describes you, please see this post
and this post
for what you can do to change calibre's behavior.
Second possibility: you want calibre to do leading article detection on the library view, but you want books on your 300 to be in strict order (no article detection). In this case, change only the save_template_title_series_sorting tweak described in possibility one.
Third possibility: you want leading article detection, but you want to fix 'A is for Alibi' (and any other book with a title beginning with 'A is'). In other words, when you click on the title column to sort by title, you want 'A is for...' to sort under A, but 'A Perfect Nightmare' to sort under 'P'. To do this, you must change the tweak 'title_sort_articles' to be
I note that you live in the Netherlands. If you read books in Dutch, you might also want to add the Dutch articles to the list. For example, to add 'Het' to to the list, it would become: