I still can't understand why there's no longer a JSP forum here (still have PHP & .NET, why no JSP?)

I had a "signup" form in my photo site.... but all of a sudden about three weeks ago started getting tons of emails thru that form, I can tell it's spam.... have had that form there for about six years, and after getting maybe three emails a year, now all of a sudden have started getting about three a day... so I eliminated that form... but am still getting the "signup" emails... how can they send emails to my email address (which appears only on back-end, not front-end), even though the form is no longer there? how on earth do they do this?? is there a way to stop these emails?

(actually what I get is not technically spam.. it's just an attempt by them to get my email address (if I ever email them) so they can get my email address so they can send me spam afterwards... is my assumption....)

thank you....