Hi Seanie
I lived there about 20 years ago, only have a vague memory of a few spots!
I used to fish off the coast at East Cowes, good for Flatties, the river Medina feeds in here too, smooth to rough ground.
Sandown and Shanklin are sandy beaches which produce flatties, bass and the usual suspects, there are good long piers to fish off too (If they are still standing!)
If i remember right, Ventnor has some good rocky outcrops which you can get everything including some good wrasse.
You can't go wrong really, the island is not that big but has some cracking marks, don't remeber blanking too much!

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My old man still lives there and fishes every now and then, i'll tap him up for some info for you.