This sort of thing depends on how you define fabrication.
For example, taking quotes completely out of context is a form of fabrication, but it is unclear whether or not this fits the profile of "fabricating stories"
Also, spewing right-wing propaganda can also be considered a form of fabrication. However, whether it is Fox News doing the fabricating or not is a different question, as it might be that they're just parroting certain individuals they agree with.
It also depends on how you define Fox News. Do you consider Fox's pundits part of their news outlet or not? Because O'Reilly and Beck and the rest all discuss current events and current news, but in a horribly distorted, extremely ignorant, and somewhat amusing way.
Anyways, searching fox news fabrication or something similar on google nets you hundreds of thousands of results, but finding a set of objective sources discussing them will take more time than I care to invest in this. Let me just leave you with one example, then.
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www.guardian.co.uk]