There are loads of similar threads to this one, you should do a search for some of them. And there are loads of pedal demonstrations on youtube to get a good idea of the sound before you splash out on something based on a recommendation.
Also, "I am not excane" has a good thread with lots of pedal demonstrations, not just OD:
[url="http://basschat.co.uk/topic/138296-my-pedal-demo-video-collection-free-pedal-giveaway/page__hl__pedal%20demos"]http://basschat.co.uk/topic/138296-my-pedal-demo-video-collection-free-pedal-giveaway/page__hl__pedal%20demos[/url]
Paul