When i download files from my email on my iPhone, where do they go?

And how could i view the files without going onto my email?

A download usually is not supported unless otherwise it is an image or document or presentation or excel or PDF files.

Image > This will be saved in photos or camera roll.
Documents > if you have Pages installed ( Mac equivalent of Word ) you can see there.
Presentation > Watch it in Keynote from Mac
Excel or Spread Sheets > Watch it in Numbers from Mac

Note: Pages / Numbers / Keynote - you need to buy this app from Appstore for $ 4.99 each. Very useful apps as these applications can save documents you edited can be mailed / saved as PDF or MS Word.

PDF > you can view them in iBooks apps.iBooks is a free app and you can download from app store.

Navigate to the iphone simulator folder in your mac machine and in the folder navigate to the users/media/downloads. If i'm correct you may find it in that folder.