ZX-TEAM - A very active German Sinclair ZX81 users' group. Site offers information about the Sinclair machines and the group's activities, including news of forthcoming events. (In English and German) - http://www.zx81.de/
The HCC Sinclair GG - Large international Sinclair user group which provides support services, public domain software and emulators, also organising user group meetings and shows throughout the year. (In English, Dutch and German) - http://www.hobby.nl/~sinclair-gg/engels/index-eng.htm