A lot of people, particularly undecided voters, complain that they struggle to find good quality unbiased information so they can weigh up the arguments for REMAIN and LEAVE and then make up their own mind.
There are a number of reliable non-biased information sources which either present both sides of the debate and/or fact check the claims coming from the IN and OUT campaigns:
(1) Fullfact is an independent fact-checking charity which is examining claims from IN and OUT campaigns: https://fullfact.org/europe/.
Worth noting that 38 degrees, the campaigning organisation, which has no position on the EU referendum, is advising its members to consult fullfact, see: https://home.38degrees.org.uk/2016/04/12/eu-referendum-lets-get-the-facts/
(2) BBC news EU referendum reality check: http://www.bbc.co.uk/news/live/uk-politics-eu-referendum-35603388
Interestingly enough, the BBC EU referendum reality check conclusions have sometimes contradicted news reporting by the BBC (which isn't a great advert for BBC impartiality and accuracy....)
(3) Channel Four fact check on the EU: http://blogs.channel4.com/factcheck/category/europe
(4) King’s College London website promoting high quality independent research on the UK’s relationship with the EU. Also includes some fact checking of claims from both sides: http://ukandeu.ac.uk/