I went through Blender Guru’s anvil tutorial last week, which was a great intermediate modeling and texturing walkthrough. It covers some different modeling techniques for hard-body surfaces and introduces normal-map baking, which is something I have never really had a chance to learn.
Here is my final render of the anvil I created:
Although the final render shows various nicks and cuts, the actual mesh does not have any of those features. By creating those details in a higher-resolution mesh and then baking them to a normal map, it gives the illusion of all that extra detail.
Here is the same shot as a wireframe (with subdivisions turned on):
If you are already familiar with Blender but want to go beyond the basics and learn more about modeling and texturing, I highly recommend the tutorial!