I cherish Chairish.
Where else can you find a perfectly matching but mismatched stack of vintage books from France? Or THE perfect mid century chairs (in perfect condition) for your entry way?? Unless you have the time to search the whole world/internet/every cool flea market in the world (that is not in the city you live), I recommend you head over to Cherish.
The site has everything from books, to the bookshelves to put them on. There is vintage jewelry, home decor, table top, rugs - all easily searchable to time period, style, or even most favorited.
OH!! And you can also make an offer to negotiate the price. It helps, if the vendor is flexible, to offset the sometimes pricey freight charges (although I will say that the "white glove" delivery service was amazing. The furniture I bought shipped fast, and it was worth every penny I paid)
I picked up these midcentury chairs a few months ago after a to New York. I sat in a set of chairs at our hotel that won my heart... and thus the mission began. I'm so grateful for Chairish where I found an almost identical set! I love the knotty thick grey fabric and the warmness of the wood. Also- they are the most comfortable chairs we own! They pull the whole entry way together- now we just waiting on my painting to get back from the framer, a rug, and we are good to go!
I'll post the whole room once it's done with links to everything!