Hi W Cleveland,
You've probably had replies already but just in case you haven't.....
I will be walking St Olav's Way in June 2016 & found the lack of a guidebook was making planning
very difficult. I eventually found the following info quite by accident!
Alison Raju has written a 2015 edition English language guidebook to St Olav's Way.
It's called 'The Pilgrim Road to Trondheim'.
It is only available through the Norwegian museum which published it.
You can order it through their website or send them an email. The online ordering
page is in Norwegian but with Google Translate, I had no problems completing the form.
You can also order it by sending them an email in English.
It's quite expensive (I ended up paying AUD$80 incl postage) but for me it was an
essential purchase & right up to date.
The details are:
www.museumsforlaget.no
Navigate your way to the bookshop (bøker)
Their email address is:
post@museumsforlaget.no
Best wishes with it.
I'd be interested to hear how you got on.