You'll see more WiFi signs than actually working WiFi hot-spots around the city, unfortunately. Here's a bunch of places where the WiFi actually works, and does so at an acceptable speed.
Amir Temur Str. C 4 No. 7/8, Toshkent, Toshkent Shahri
Hotel · 48 tips and reviews
Rene: Just hang around in the lobby, there are electricity plugs and the WiFi works fine. Avoiding to order any of their grossly overpriced drinks is easy.