I'm very new to ASP myself and I've found some things elegantly simple. I'm using a session variable to pass info from one page to another. I started using a cache variable, but came across situations where the cache would cross the 'boundaries' of multiple users. (one user's cached information would show in another user's session)
Basically, on my calling page:
Session["USEREMAIL"] = this.txtEmail.Text.Trim().ToUpper();
And if I want to compare or use that on subsequent pages, i just compare the Session["USEREMAIL"].ToString():
I know there's some added overhead with session variables, but like I said, I'm new to all this. I'd like to get the application working first, and then work on improving performance.
I hope this helps.