That's quite a vague question. The point of the macros are to automate mundane stuff, so it really depends what you want to do. For that reason, there is no list of common macros. However, if you want a good source of things that are possible with macros, you might want to have a look at some of the workbook examples on Stephen Bullen's Excel page:
You can view the code that he created for each example, but it will be hard to follow. The best way to learn VBA (the macro programming language for Excel) is to come up with a problem and try to solve it.