Passing Parameters From Form To Queries

Good Afternoon,

I am trying to create a form where a user will enter in a value into a text field. Afterwards, when the user clicks "Enter", a query will run and will LOOK FOR THE VALUE THAT WAS ENTERED INTO THE TEXT FIELD. i.e.
User enters their address into the field and clicks the enter button.
Afterwards, a query will run like
select * from customers where address = @address <== the value the user entered into the text field. This is where the mystery lies. How do you pass values?????

Thanks,
Nervous Jervous