I got a great waterproof, 'shockproof' (within reason) cover off ebay for £8.
It has a replaceable seal/grommet and they offer lifetime exchanges for faulty items. (Not normal wear and tear)
Looks good, performs great and keeps the phone usable for GPS, texts, calls, pics etc
I submerged it in the sink for an hour before first use, go out in all weathers and it still has never let any water in.
Chris