php & asp.net sessions

[peraonline]

Hi guys,

I am a PHP programmer, and when I want to create a session, I call a Session_start() function that make a session ID, send a Cookie to the client, ecc.

What can I do this in ASP.NET? why the session always starts when the application starts and not when I want that starts? my reasoning it's complicate, oh yeah

Finally, where can I find a GOOD guide to session in ASP.NET?

THANKS

Matteo