here you are

Answer:
duffaboy gave you a good site and their are a few others that work the same way … unfortunately non of them will work properly if the person you're checking has a checkmark on the Only People on my allow list can see my status and send me messages ( in the privacy list ).

Keira01001 did have a point too .. usually if i think someone blocked me I'll just send them an offline message and see wether they reply or not :)

Answer:
you wnt be able to start a conversation with the person