Welcome, Mariepet! Congratulations on your new home and space to plant things that bring you joy. It is very exciting!
It would be best to save your spaces for fall planted peonies. They acclimate better and are well worth the wait. Much of what is typically available at greenhouses is mislabeled. It's easier to plant annuals
and saving these coveted spaces for the ones you really want.
Some of my favorite places are Song Sparrow (out of business after this year), Solaris Farms, Adelmans (in Oregon), Fina Gardens, Parkers Perennials, Oh My Peonies & Hiddensprings Farms and Gold City Flower Farm. I have also heard great things about Lyndaker Farms, but haven't had the opportunity to order from there myself.
Enjoy your gardening planning.