Are you familiar with the default page for Suggestions, Dave? That page has various search parameters available, including location.
If you have a specific misspelling that you want to find, you should be able to search for it from the default Suggestions page.
Yes, Location errors are 600's.
Location errors are split into 3 groups as follows: 601-630 Birth location, 631-660 Death location, 661-690 Marriage location. Some errors can be defined by users Space:Database_Errors_Definition.
Not all spelling errorrs are caught (yet). One can also analyse location spellings on Wikitree+: Analyse - Location.
As an example, here is the analysis for the city Zierikzee in the Netherlands.