Everytime I try to register on the trenitalia website I get the message "email in use)...I have used different email addresses and I keep trying at different times. has anyone been successful? I want to get the deal on an ICN train rome to venice for 45euro a piece--how else can I get this train deal?

You can get the Rome to Venice ICN train for as little as 15 Euros in reserved FIRST CLASS, with the "Freedom to Travel" promotion. For 45 Euros, you could get a "Comfort Class" couchette bunk (C4) or a sleeping compartment (twin or triple occupancy).