Tutorial update: another tutorial completely rewritten with more information this time on "
Mesh Display (Numerics) in Blender (https://www.katsbits.com/tutorials/blender/edge-length-face-vertex-normals.php)" (formally "
Edge Length, Face & Vertex Normals properties in Blender"). Now covers edge length, face area, angles etc. and vertex/face normals in Blender 2.49 or below, Blender 2.50 through 2.65 and Blender 2.66 up to and including latest. Updated eBook also available (https://www.katsbits.com/store/index.php?act=viewProd&productId=42).