Mel, it's good to have you with us. I hope you enjoy your time here; it's a friendly group with lots of different levels of experience and areas of interest, so find a discussion that interests you and dive right in! If you have any questions, you'll find those welcome as well -- there's a wealth of modeling knowledge we all pretty much love to share.
As to posting photos, for this forum they need to be hosted on some 3rd party site like Postimage (just an example, but it's one that's free, and easy to use). Then just copy whatever link that host site provides, and paste it into the post you start on this site using the "Edit image" button (the mountain scene icon) in the task bar above. It should pop right up. (Note that the forum has a "Test" section where you can try out links and such.)
If you have questions related to a specific host site -- since their mechanisms are all a bit different -- just mention the site in your post title, and someone familiar with that site is bound to chime in.
Cheers