Glad you found what you wanted Ina. I was going to suggest McAree in Edinburgh/Stirling too, because their online shop is always well stocked and although they don't go for the sensational discounts that other sites do, they always have what you look for, and in big quantities. Never had a single problem with them in over a year I use the site.
I had heard about knitting jumpers in the round too and actually have just bought myself a long circular needle to give it a go, although the amount of good yarn (with a high wool content) needed to make one in my size is so astonishingly high (in 50g or 100g balls), that makes me cry (and my bank account too).
I have received today two free patterns to knit in the round from Jamiesons and I swear I'll make one - takes what it takes!!
If you also want them, you can PM me or email Jamiesons directly and they will send the pdf.