Hi nanapippa
I happen to live close to this wool shop so I'm lucky http://www.madewirral.co.uk/yarn/ but if you google Bergere de France you may be able to find a stockist near to you. I do know that there is a shop in Port Madoc, North Wales on the main road moreorless opposite the station which sells all the yarns but unfortunately I can't remember what it's called - I only found it by chance when we were visiting for the day!.
As to the patterns - I've never seen any individual ones in the shops, they all seem to come in magazine type books which cost about £5.00, but single patterns are available if you can find a stockist. If you have a look on-line some of the web-sites give you the option of clicking on each of the patterns in the books so you can see whether there are enough of them you might like to knit to justify the cost.
What got me interested in the brand was a couple of patterns that were in a Love Knitting for Baby magazine earlier this year - these used Caline which I think moreorless equates to a fourply wool. Ciboulette only seems to be available in traditional baby colours but there is a much wider range of colours to choose from in Caline