You will find a lot of online shops, which sell discs online.

I will just list a few here which have a incredibly wide range of discs, generally ultimate discs.

USA

Amazon.com – discs from different sellers

The Wright Life – lots of disc, some collectable items

Internet Disc Shop – selling ultimate discs since 1994, some lovely designed team discs for sale

Discovering the world – lots of flying discs for all sports, own designs

UltimateDiscstore.com – cheap prices for discrafts, ultipro and Daredevil discs.

Europe/Germany

New Games – Frisbeesport –  biggest selection of flying discs online in Germany, sell their own style of discs – eurodiscs for ultimate

Amazon.de – discs form different sellers