I am building a roof 50 x 18 to cover an existing deck. I have 17 timbers 6x8x18 made of hemlock. I've read online that each of these timbers weighs approx. 370 pounds. My questions....what is my best bet for attaching these timbers to my ledger ?? They will be resting/secured at the other end to LVL's
This is an impossible question to answer on the internet. This needs to be seen by someone with structural engineering expertise and your local building codes.
There are multiple issues involved with this structure and you've only addressed one.