People have asked me many times how to save PDF files to their iPad that they view online. If you have the GoodReader app on your iPad then this is very simple. When you open a PDF file with Safari just add the letter g in the front of the address and hit Go. Trust me, that's all there is to it. That PDF will then automatically download into GoodReader.
Here are step-by-step instructions from the makers of GoodReader.
To save a file from Safari to GoodReader:
• open the file of interest in Safari
• tap Safari's address bar (the keyboard will appear)
• go to the very beginning of the file's URL address, where the http:// or https:// part is
• add a single letter g in front of the address, so you'll get ghttp:// or ghttps:// instead of http:// or https://
• press Go on the keyboard (this will close Safari and start GoodReader)
• the file will start to download into GoodReader automatically (check Web Downloads section to find it)