I'm 6ft tall so I ride 58cm (23in) racing bike converted into single speed).

However in case of fixed gear bikes, especially for learning the tricks, many people recommend smaller frames

According to this youtube video:

Bike Sizing: Laying down the law on how to properly size yourself up on a fixed gear bike

(I can't post links)

my frame is too big because my 'basketballs' hang on the top tube

Any comments ?