Londonist are starting to think their city is getting just a little bit too expensive, when even Christian Slater can’t afford to go out there. And there’s no escaping, as local singer Lily Allen discovered when she was barred entry to the US. The British mapping agency caused further bad karma, by blocking a 3-D representation of London in Google Earth. But the smiles returned to Londonist’s faces as they interviewed Baroness von Reichardt,…