I know Gordon Dickson has written a range of science fiction and fantasy novels.
I particularly like the world described in ‘Jamie the Red’ - a mixture of medieval technology and some magic, perfect for giving me roleplaying ideas.
Can anyone tell me if there is a followup novel, set in the same world?
I’ve never read “Jamie the Red”, but I seem to remember the world from “A Dragon For Saint George” being similar to what you described. (I haven’t read or even seen this book in years, so I may be way off, maybe even the title and author.)
Jamie the Red was the character Dickson originated for the Thieves’ World shared universe stories.
I have a vague rememberance of a follow-up after the whole shared universe game got lame…
Okay, so the old memory is not what it used to be. Dickson never seems to have gotten around to writing his Thieves’ World story, although Jamie appeared in Poul Anderson’s contribution.
There was a second Jamie book by Dickson. Beyond the Dar Al-Harb
I know nothing about it except that it is a penny book on Amazon’s Marketplace.
Correct. He first appeared in “The Gate Of Flying Knives”, a story in the first Thieves’ World book.
Thank you all for your replies. Happy New Year to all. 
I have ordered ‘Beyond the Dar Al-Harb’, and will dig out my Thieves World collection!