I'm having problems uploading pictures

If you are having trouble uploading pictures, it is likely because they are over 750Kb in size, or are not in the .jpg format. 
Currently photos must be only in the .jpg format, not .jpeg or any other file type.

If you do not have software that can compress the images so that they are smaller sized files, you can use http://picresize.com to resize the photos pretty easily or you can open a free photo storage account someplace like Photobucket and upload the photos there, then insert them into the body of your listings.

Otherwise, you might want to check to make sure your computer has the latest version of Java:
http://java.com/en/download/installed.jsp