As you had already secretly longed for in your latent heart, Diagon Alley is now explorable in Google Street View, in all 360 degrees of glory (more accurately, it's the set of Diagon Alley from the Warner Bros. studio tour in London, but let's not get nitpicky because that will ruin the magic). Go ahead forth and virtually explore — but don't take a wrong turn or you'll end up in Knockturn Alley with a spotty goblin mouth-breathing on you.
The Warner Bros. Studio Tour was AMAZING, far better than the Harry Potter theme park in Florida in my opinion. It was great they had all the videos about the creation of the special effects, and all the random facts about the sets.
For instance, they built the Gryffindor boy's dorm to the size of the then 11-12 year old actors for the first film. By the sixth, their legs were all hanging off the end, so they had to adjust their camera angles accordingly. I thought that was ADORABLE.
Also, the Potions classroom with all the labelled jars was incredible, as was Dumbledore's office and Umbridge's office and Hagrid's hut... I'm going to have to go again soon!!!