Have a name listing, would like to start a new page with each change of the first letter. Can it be done? Have tried various methods but nothing works. Have a Writer document with a long table.
A table cell is internally managed by LO Writer which optionally inserts a page break when cell content overflows current page, if this is allowed by Table>Properties, Text Flow tab. Other than that, any attempt to play with page or column layout within the table is ignored.
The reason behind it is a table implicitly creates a frame which is an atomic object attached to a single page. If table fractioning is enabled, text flow creates linked frames for overflow content.
Your only option is then to use separate tables for each initial letter. Unfortunately, I don’t know of a trick to break a Writer table into several consecutive tables. Create then your tables and copy/paste content from your initial one. Afterwards, delete the redundant rows in the original.
If this answer helped you, please accept it by clicking the check mark 
to the left and, karma permitting, upvote it. If this resolves your problem, close the question, that will help other people with the same question.