I logged into my email account via this link:

https://bis.na.blackberry.com/html?brand=mycingular

but I can't find an option to view my emails anywhere. Where would I go to view my emails on a desktop? (Cingular/AT&T)

You can't use BIS to view email. You need to use an application such as Outlook or use the BB itself.

Or integrate an email account that has webmail access (like gmail, Yahoo, etc etc). Don't use the *.blackberry.net address for anything but forwarding.