Are you trying to post to the gallery? You need to be sure that you're in your own personal gallery space rather than an index page. Make certain that you're logged in (look for your name in the upper left of the page, then just above that there's a link to "My Photos". Follow that link to your gallery space where you can upload your photos.
Here's a little photo tutorial I've put together:
You don't need to buy any special software to post pictures here. If you want to resize your pictures there are several different freeware programs you can get such as Ifranview, Gimp or Paint.net. As a member of Aeroscale you have a space in the image gallery (look at the black bar on the top of the page. The Gallery is found between "Events" and "Links" on the right hand side of the screen. Follow
this tutorial to use it.)
The only problem with the gallery is because we have so many members it can't hold many pictures so many of us use another photo hosting site like Photobucket, Imageshack or Flickr to host our pictures.
Regardless where you host your pictures, the way to insert an image is pretty simple. Whenever you're writing a post, you'll see 7 little white buttons just below the area you type in. the far right-hand button says {img} (except that the brackets are square). Click that button whenever you want to insert a picture and you'll see this appear:
{img}http://put.url.here/image.file{/img}
(once again, the brackets will be square in real life)
Go to your image hosting site, select your picture, and copy its URL. The fastest way to do that is to hover your mouse pointer over the picture, click the right mouse button and select "copy image location" from the little menu which pops up.
Come back to Aeroscale, and replace the text which says "http://put.url.here/image.file" with the URL that you just copied. I like to use browser tabs which let me easily switch between Aeroscale and my hosting site as many times as I like. This is useful for inserting multiple pictures in one post.
Enjoy your stay in Aeroscale. If you have any questions at all, all of us will be happy to answer them. Happy building!