What are good websites that reference vintage?

Buying Guide:

Basenotes.com Grant has produced some of the best user made forums regarding the fragrance community. Basenotes is an excellent hub for the experienced collector. 

Fragrantica.com is the largest perfume database online. I find their "reminds me of" section, very helpful for discovering new vintage scents.

Raiders of the lost scent.blogspot.com Andre and his team have created an incredible database and community blog for how to decipher batch codes. This is expert level work when deep diving into vintage perfumery.

Check fresh.com is a great tool for dating modern batch codes.