Create new user page - Store in SQL express

Hi,
 
I like to create a new user webform. I like to have multiple textbox fields for the new user to enter and would like to use the inbuilt ASP SQl express to administer. Can someone please help how this can be done. I read somewhere to use Membership.CreateUser API but not sure what that is?
Is it as simple as dropping textbox in a webform and in webconfig options place a line of code?
I am a newbie, please be gentle.
Nijojo.  
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