How cam i use the bump map

#1 I would recommend reading the documentation for TGEA and creating your material.cs file accordingly. I believe the docs (or TDN) has an example.

#2 Keep an eye on this blog and the follow ups. It's not going to be a material library only, but also a fairly straightforward how-to do it yourself.

Basically what you need is a diffuse map (color) and a normal map; the term 'bump' is both inaccurate and obsolete. Then you have to write up a material.cs file with all your models' materials (if more than one); Look here for the docs section regarding materials.

#3 You can make bump maps with the nvidia plugin to photoshop i use it and its realy easy to make