You can easily do what Gene suggested, or if you wanted to use photobucket to host them you could too. I like using photobucket, or similar services because there is no size restriction and I can easily post them on any forum or message board I want. But it really is up to you on what you want to do.
You can link to them from photobucket. What you would do is go to your photobucket page and you should see something that lets you choose a picture from your computer. Find the picture(s) you want and the size of picture you want to upload, and click upload. Then wait...if you choose to have the pictures a small size, it will be quick. A large size will take a while unless you have a fast upload connection. After that its pretty straight forward. The pictures will be in your 'album' and underneath each picture are about 4 different boxes. Click the one that says 'direct link' and then you can come to your post, click ctrl-v or apple-v and it will copy the link to your photo into your post. Or you can select all the pictures you want by checking the boxes next to them, then scroll to the bottom of your album page and click 'get html links' or something like that. Copy and paste the one it recomends for forums/message board
