Welcome to the forum! The X100 is an awesome camera indeed!
To post photos, you can do it in a number of ways (that I am aware of)
(1) Click the "gallery" tab on top of this page. You should see an "upload photos" link to the top right. Once you've uploaded a photo and you click on the photo, there are two links towards the bottom of the page: one says "linked thumbnail" and the other one says "linked image." Copy the link (whichever you prefer) and then insert on the body of whatever message you are composing.
(2) If you have a Flickr account, go the photo you want to post, click on the pull down link that says "share", and then copy the link under the "grab the html/bbcode" option. The paste that link to the message you are composing.
Hope that helps! Looking forward to seeing your photos!