Plugin that saves form data

Do you mean how you can display the form on your website? If so, write a shortcode for it 🙂 http://codex.wordpress.org/Shortcode_API

Edit: Oh and you might want to add a hook so your function that saves the data is triggered. add_action(‘init’,’rchs_add_donor’) should do. And add a check in your function to check if your POST is set.

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