I've happened on these two websites at different times in recent history and was completely thrilled to find such wonderful resources.
On Fragantica's website, you can search by designer to learn more about your perfume. You'll find out when the perfume came out, a description of the fragrance, what the top/middle/base notes are, and how the sillage/longevity rank.
On Bois de Jasmin, you have a professional post about new perfumes or perfume best practices. Her search tool on the right-hand side or search bar at the top right will help you locate information quickly. I often get lost in her posts enjoying not only her writing style and tips, but the expert yet not condescending reviews and reactions. She's very honest, very approachable, and makes learning more about new perfumes fun.