http://www.wowwiki.com/Making_a_macro
http://www.wowwiki.com/HOWTO:_Make_a_Macro

->

http://www.wowwiki.com/HOWTO:_Make_a...ells_and_items

[edit] The reason why people don't explain the whole macro in detail is because you're supposed to know how to write macros yourself (so you can read and understand the ones of others).