Refactoring elisp code that generates files

I wrote a simple emacs module that generates standard templates that I use for my blog's static site generator.

(defun hakyll-site-location ()
  "Return the location of the Hakyll files."
  "~/Sites/hblog/")

(defun hakyll-new-post (title tags)
  "Create a new Hakyll post for today with TITLE and TAGS."
  (interactive "sTitle: \nsTags: ")
  (let ((file-name (hakyll-post-title title)))
    (set-buffer (get-buffer-create file-name))
    (markdown-mode)
    (insert
     (format "---\ntitle: %s\ntags: %s\ndescription: \n---\n\n" title tags))
    (write-file
     (expand-file-name file-name (concat (hakyll-site-location) "posts")))
    (switch-to-buffer file-name)))

(defun hakyll-new-note (title)
  "Create a new Note with TITLE."
  (interactive "sTitle: ")
  (let ((file-name (hakyll-note-title title)))
    (set-buffer (get-buffer-create file-name))
    (markdown-mode)
    (insert (format "---\ntitle: %s\ndescription: \n---\n\n" title))
    (write-file
     (expand-file-name file-name (concat (hakyll-site-location) "notes")))
    (switch-to-buffer file-name)))

(defun hakyll-post-title (title)
  "Return a file name based on TITLE for the post."
  (concat
   (format-time-string "%Y-%m-%d")
   "-"
   (replace-regexp-in-string " " "-" (downcase title))
   ".markdown"))

(defun hakyll-note-title (title)
  "Return a file name based on TITLE for the note."
  (concat
   (replace-regexp-in-string " " "-" (downcase title))
   ".markdown"))

Now, this works, but it could do with DRYing up a little bit, but I don't know enough elisp to do it myself.

• hakyll-new-post and hakyll-new-note are very similar and could do with DRYing up, but I'm not sure how to pass the correct parameter to any refactored function
• I'm hard coding hakyll-site-location. Is there any way that I can request for and store a configuration in my emacs dotfiles?

Any help or pointers to documentation are welcome.