Not a 3D tutorial on how to make the eiffel tower, but some reference images that could help if you decide to model it.
You'd need to learn some basics of 3D modelling. Extruding, usig ref images etc.
The Anim8or manual will help, and other 3D modelling tutorials. (google)
It'll be a challenging journey, but you'd learn a lot by putting some serious time into this project.
Good luck.
The 'shape' could be modelled, and the laticework of beams could be done with textures.
Will take a bit of working out to get it 'four sided'.
If it's too much, you could find a free 3d download of the eiffel tower, and upskill your modelling by doing some slightly easier projects to start with.