Replace/alter/rename form labels in theme I installed this Simplenews module, and it gives default field to enter your email to subscribe for newsletter and the fields title is just 'Email:' and I need to change it to something else. 

It looks like it's hardcoded and I could just dig through modules files and edit, but I know this is not recommended.

I was hoping maybe I could just paste in some preprocess function to theme's template.php file and replace 'Email:' with e.g. 'Join Our Mailing List:'. 

Path to label is form.simplenews-subscribe div div label.
Solved!

Put this code to your theme's template.php, where's THEME replace it with your theme's dir name. So then where's #title = t() you put in your own custom title for the field. So what it does it alters given forms field, in this case it's simplenews_block_form inlcuded in between THEME_form_simplenews_block_form_alter

function THEME_form_simplenews_block_form_alter(&amp;$form, &amp;$form_state) {
  $form['mail']['#title'] = t('Join Our Mailing List:');
}


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