Performing a find with special characters in it

I trying to write a custom php web interface with my existing website so that potential customers and sign up to recieve our news letter. I have created a database with fields for email address, name, mailing address, and interests and subscriber status. customers do not have a problem coming to the website and signing up, however, I have also written an unsubscribe. where a customer may go to a different page, enter their email address, and the database scrip performs a search, finds their record based on the unique email address and automatically switches the subscriber status to "do not contact". I can not execute a search with the full email address in it, and it seems to be because of the @ symbol. however i have noticed that I can remedy this by doing searching with quotations like "[email protected]" and it will properly return a record for that email address. is there a way to do this without using the quotations, and if not, how do i write a find script to take the regularly entered email address and transform it to the email address with quotes around it an then execute the search.