Making PDF File Sizes Smaller

Is there a way to make the size of pdf files to be a smaller file size. The file sizes that you get from the print menu are too big. I know about altering the image size with the Automator script in PDF services, but this doesn't get them small enough. Is there another way without having to get a third party app like Acrobat, PDF Compress, or PDF Shrink? Any help is appreciated.

Thanks,
Barry