Every picture on the web has a web address (url) ... just like the site that hosts it. The web address for the homebrewtalk web logo is:
To find this you simply right click on a picture in your browser, then click properties.
Once you have that you put it in img brackets on this forum like so
[ IMG ] the url [ /IMG ]
But without the spaces between the brackets, I put those there so that the message wouldn't think it was an image I was trying to post.
There are many places you can upload images from your computer for free. Imageshack, I believe. Anotherprofile.com, myspace.com. Once your pictures are uploaded there, just right click on them and get there URL.