A lot of them give you shitty Windows whether you want it or not,
wondering if anyone knows of one of these websites in the UK that
perhaps doesn't force Windows and also is Linux friendly - that is to
say they know the hardware works on the Linux kernel already.
I bought my last PC from Open For Everyone  - I e-mailed them with a
spec, and they sent me a price, which didn't include Windows (but did
include Ubuntu) and was cheaper than the other sites I checked (all of
which would have included Windows)