Javascript doPostBack function in Classic ASP and submit values

I have a classic ASP page that needs to do a post via javascript doPostBack function in order to assign a value in a hidden variable. Basically check out this page [[login to view URL]][1] What I want to happen is when the user clicks on Select This Package (on either the Standard or the other column) it needs to run a javascript doPostBack function to assign the value of the column selected to a hidden variable. (You will need to create this hidden variable - it currently does not exist on the page.) Then when the user clicks on Proceed to Secure Payment button it needs to submit values to PayPal based on the value of the hidden variable. (I have already programmed the values that need to be submitted - they are at the top of the page in javascript function Validate(frm). This function will need to be adjusted accordingly based on the value in the hidden variable.) For example, if the hidden variable stores Standard - then the set of Standard variables will be submitted to PayPal. If the hidden variable stores Premium, then Premium values will be submitted to PayPal. I need you to provide the code for javascript doPostBack function, the hidden variable and the javascript that picks up the value from the hidden variable (when the Proceed to Secure Payment button is clicked) One more thing - if the user has NOT selected a package by clicking on the Select This Package, and clicks Proceed to Secure Payment, then it needs to provide a pop-up box saying Select subscption package. IDEALLY IF YOU COULD POST THE SOLUTION, I WILL TRY IT AND IF IT WORKS I WILL AWARD YOU THE FUNDS I know this is easy!! It should take only a few minutes for someone who is skilled in javascript. The solution needs to be cross-browser compatible.