I have one long list of Japp family members who moved from Scotland to Utah in the USA. This list is posted on my Japp Family Genealogy website. I don't have any information about Alexander Japp in my branch of the USA Japp families. Over 96 people with the Japp surname entered the USA between 1892 and 1930 as well as many before that like my ancestor. I have read about a Alexander H. Japp who authored of a book about Robert Louis Stevenson, but I don't know his exact genealogy.
I now have the new URL pointing to the Japp Family Genealogy website. You can now use
www.japp.org instead of
www.jappgenealogy.org and you will be automatically forwarded.