How to submit two forms at same time?

Question

Have a client that requires their members to update their profile information and some of the details from that form need to also populate a WebApp.
I've seeded the CRM with basic (first name, last name, email address, Your ID, and EntityID) member data.
Members would log in and be asked to update their profile. [action="/MemberProcess.aspx"]
This submission should update their CRM record *AND* create a WepApp record at the same time.
I tried the AJAX + jQuery method, including the second WebApp form [action="/CustomContentProcess.aspx?...] fields as type="hidden", and using {tag_FIELD NAME}; but this isn't working for me, I'm admittedly not a real programmer.
Any thoughts? Thank you very much, in advance for any and all help!
p.s. the reason for wanting to do this, is so that members do not have to update their CRM profile and then also input their data specific to the WebApp form (it's a member listing) as a separate task.
p.p.s. after I get through the above hurdle... how can I ensure that a CRM user has one and only one WebApp item (their listing) and that they can edit it? Another issue I'm having now is that users create a new listing in the WebApp if they submit another record and in the future I fear that simply editing their CRM profile will create new WebApp listings too. This site is like a phone book, there should only be one listing for each unique email address (in this case).
-Will

Answer 1

You can use Jquery + AJAX to submit as many forms as you want to as many places as you want. Don't use the HTML to submit and have a second javascript submitter as the Javascript might not have time to complete before the page is submitted.
I wrote this quickly just now, this wont work on the JSfiddle site because you can't form POST / GET anything on it (AJAX included it seems). it will submit to other URLs the same data. It is done in parallel and because we don't know which one will finish quicker, both calls check if all calls are complete before confirming everything is complete. I have not tested it but it would get you 99% of the way there.
<form id="signup_register" action="" method="post">
    Firstname<br/><input type="text" name="firstname"><br/>
    Lastname<br/><input type="text" name="lastname"><br/>
    <button onclick="formsubmit(this);">Save</button>
</form>
<script>
    var url1='http://google.com';
    var url2='http://gmail.com';
    var complete1=false;
    var complete2=false;
    FinishedTwoFormSubmits=function(){
        alert('Finished submit - redirect or whatever you need to do.');   
    formsubmit=function(el){
        var data = $('form#signup_register').serializeArray();
        PostSubmit(url1,data, function(){ complete1=true; if (complete1 && complete2){ FinishedTwoFormSubmits() } });
        PostSubmit(url2,data, function(){ complete2=true; if (complete1 && complete2){ FinishedTwoFormSubmits() } });
    PostSubmit=function(url,data,cb){
          var ret=false;
        var noerror=false;
                    $.ajax({
                                type: 'POST',
                                url: url,
                                cache: false,
                                data: data
                              }).done(function(msg) {
                                        try{ noerror=true; }
                                        catch(e){ alert(e+'\n\n'+msg); }
                                        if (noerror){ cb() }
                    return ret;
</script>