Irrlicht Engine

How can I convert my mesh to tangent normals in blender? I don't want to generate normal maps or anything I just want tangent type vertices.

huh?
Do you mean you want to use blenders glsl materials in the 3d view?

I don't want to have to use the mesh manipulator to create a tangent mesh when I load my model.

This isn't necessarily a blender thing, you just have to convince one of the loaders to load your mesh with tangent type vertices. This would work with .irrmesh format, so maybe check whether irrb can export to tangent type. Other ways are to create a bump mapped mesh and load it with 3ds or obj loader, which both support this type of material if properly exported. But the simplest way is to use the mesh manipulator