Well for a start... are you the "intelectual owner" of these macros?
i.e. if you have written them while employed by someone else, the macros are their intelectual property as at the time you wrote them, you were employed by them!
So I would believe that you would need their permission to sell this information.
If you are self employed, you would be selling your strengths to others in the same market as your self! What is the easyist way to make more money than your rival? Make things quicker and easier than they do!
Macros make this much easier to accomplish as they help with making sure your programs run smarter and easier than what anyone else's do!
I, personally, have no problem helping out people with specific questions, rather than general "how do I do this?" types of questions as I think most people would agree, you need to help yourself a little before others are willing to help you.