Thanks so much everyone for all the extremely helpful feedback

Jennie, if you have the book I know it must be a good 'un - I've seen the lovely marbles you make

I've been browsing YouTube and I have that edition of The Flow too... but I need a definitive tome that I can sit and read away from the computer...
Cindi, I have that tutorial in my Etsy favourites too

Sue, of course you can borrow it

Will you be at the Flame Off this year? If I have the book by then I can bring it with me so you can have a quick browse...
Jean, if you ever find out which mag it was, let me know and I'll search for back issues

Emma, I've been right through both here and LE, trying to digest as much info as I could! It seems wherever I went lead me back to Drew Fritts book... I guess I didn't really need to ask on FH but it's always nice to have a bit of reassurance

OK. Time to dust of my credit card...

Thanks again!