We went last year and will likely go again this year. We flew with Monarch from Manchester (quite cheap) and camped there. Many others we knew stayed in Barca, you can get the train out to Montmelo and its about half hour from the station to walk. Would recommend camping if possible, cheap and right next to the track. General admin is good you can get some great views.
If anyone is looking for a ticket… I have a spare Gold 4 ticket for the weekend.. was meant for a family member who can’t attend.. let me know!! :)