As long as its clear
you probably don't need a 'special' form. I'm assuming you are a tenant at will. In many states renters can be tenants at will, which means either the landlord or the renter can termoinate the relationship with 30 days notice. Sometimes leases are written this way. If you formerly had a lease and you never renewed it when it came due again, you are also a tenant at will.
If thats the case just send a certified letter to your landlord that you will be moving out on June 30th, 2006 and your landlord should consider this letter his 30 day notice. You should arrange to return the keys to your landlord or someone who represents him on that day. You may want to give him a forwarding address so he can return your security deposit. Sending a certified letter gives you proof that your landlord recieved the letter and was notified that you are moving out.
Best,
Ibis