Last year, I harvested my wet hops, vacuum sealed and froze them.
Then I made my wet and hoppy porter, and started tossing them in at 30 min > 0 min.
I used them all up in one 20 gallon batch, and the result was outstanding, unfortunately completely unrepeatable, but still outstanding.
Use a known bittering hop that you get in a bag, then just dump em in a bit at a time.
BYO mag has an article this month that said you should use 5 to 8 times as much as dried hops and they recommend that they are used in the last 20 mins.
JQ