[Aetae]

Только contains'ом это не сделаешь, надо в ручную фильтровать:

<span class="price">101 200 <span class="currency">руб</span></span>
<span class="price">0 <span class="currency">руб</span></span>
<span class="price">500 100 <span class="currency">руб</span></span>
<span class="price">10 899 <span class="currency">руб</span></span>
<span class="price">23 200 <span class="currency">руб</span></span>
<span class="price">13 213 <span class="currency">руб</span></span>

<script src="http://ajax.googleapis.com/ajax/libs/jquery/1/jquery.js"></script>
<script>
  $('span.price').filter( function(){
    return this.innerHTML.charAt(0) == '0'
  }).css('color','red')
</script>