Never camped in cornwall but fished there.
A good spot to fish is near the Headland hotel in Newquay.
If your that way its worth a go.
If you drive to the Headland hotel it will be on your right hand side, just after it is a right turn. Turn right there and drive to the carpark at the end of the road.
Just so you know you have found the right place there is a dis-used RNLI building and ramp there.
Anyway, when you park up theres a beach on the left (never caught from there
) And a large hill in front of you. Take a recky around the hill and you should find a good spot.
There is a cove on sead hill on the right hand side that ive had a fair amount of sucsess from.
Macarel,gurnard and wrasse to name but a few.