Sourcing plants, logs & rocks

Hello all! I have two planted tanks (50gal, &30gal) but I also want to set up a very small 5gal tank of just plants and maybe a few shrimp for funsies. Where do you get your logs, rocks, and your fave online source of plants that come un-melted (have had issues with online sources ). I love the scaping part of the whole thing but HATE the sourcing. I am always second guessing if the logs and rocks are safe for the fauna in my bigger tanks. Thanks so much for your help!!