i'm reading through the entire org-mode manual. i've used it for years—it's time to master it.
org-mode has excellent support for handling links to other documents, both local and remote. in addition to a rich vocabulary of link types, if you're in a document—for example, a source code file—and you want to insert a link to a definition in that document into an org document you are working on, you use org-store-link to create a link to that definition—the type of link created depends on the type of document in the current buffer. you insert the stored link into the org document with org-insert-link. this works for most common emacs buffers (org, email/news, etc.).