Assuming you have Picassa loaded and set to pick up images on your desktop you do the following. You go to Picassa back to library and click on the original photo which will open it  and may be 3 megabites.
After you open the original photo you click on export on the bottom right of Picassa set to 600 pixels and either normal or minimum.
It will then open its own folder  with the reduced image. If the image is in another folder click on the folder to release the image. Then drag it to the desktop.
You then reopen Picassa library and miraculously there will be a folder which says desktop which will include the reduced image. You then open it and send it to your web album assuming you have a g mail account. I always send it to a folder that says do not delete since if you do ET will lose the image also.
Et voila. You find the link to this photo set it at 800 or 400 if you want it  smaller and paste the link into ET

Hey, Grandma Moses started late!