B&Q seedling and cutting soil is good and fairly inexpensive.
i used morrisons seedling and cutting compost on my last grow and i found it brilliant!and its only 40 litres for like 2.49 pretty good deal i think.
or you could order online from a hydroshop.
hope you find soil.
peace out man
I just used B&Q multi-purpose compost, 2 150l bags for a tenner if it's still on offer. I don't thnk its the best but its working pretty good for me at the moment. make sure to get loads of perlite too