When I had a SE I used to use a free program called Audacity to chop up parts from MP3s for use as SMS tones. Quotes from your favourite movies are good too.
I had "English mother f******, do you speak it?" as mine for a while! Then it was "I'm a mushroom cloud laying mother f******, mother f******!".
How nice
Simply Google for them. In my case it was "Pulp Fiction movie sounds".
Sorry, I dont know of any sites that provide free SMS alerts as I found making my own a lot more fun.
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