I managed to track down the cheese I was after, although I could not track it down in either of my local supermarkets, they had some in a health food shop in a shopping centre not too far away. I had to go out to do some last minute xmas shopping anyway and was pleased to have finally managed to buy some cheese!
I was thrilled with how it turned out as I didn't follow a recipe of any sort. But this is what I did:
I brought water to the boil and began to cook the pasta (you can't buy wholemeal macaroni where I live so fusilli had to suffice!)
I used 250ml of unsweetened soya milk and all of the cheese (the package is 60g and is in powdered form).
I added both and heated them together on a medium heat until the sauce began to thicken (this happened really quickly)
I used a whisk and stirred it regularly to stop it going lumpy.
I then drained the pasta and added it to the sauce until all of the pasta was nicely coated.
And then I ate it and it was yummy!
I don't think it tasted exactly like regular macaroni cheese but it certainly tasted good and will be something I will definitely make sometime again soon!