The Petrified Wood slab looks like...a T-Bone steak. Cool fossils. You're in the right place at the right time it sounds like, but it's sad to know a shop is getting closed down. I can't add too much to your query other than the western states have a lot of really nice fossil sites...I buy these fish fossils from a guy out in Wyoming who visits the local gem and mineral show here each year. They're in the same looking matrix as your 'insect' fossil pictured here. The site is in Kemmerer, WY. Arizona I think has the 'petrified forest' out there...I have a piece of reddish pet wood from out there, among some other specimens from all over.