help..validating user's emile address

[bluestar]

hello
how can i send a validation email to a user after he fill in the registration form??
the email should containa link to an asp form..and link should have a querystring...then in that asp page..the link should be validate...
but ..how is the uer registered...is he registered after he click on the link?>??i mean is his information inserted to the db after clicking on the validation link..or his information will be inserted to db as soon as he submit the form??
so after that how should i use the email for validating his address??
please help..
i need a sample code...:o

[pelegk1]

u send the user a link with his user id in the link
and he must press it
and then u update the db that the user has activated his account
and u tell the user if he dont authorize in 24 hours he will
be deleted!