I have sunglasses which are rather big (bug eye), and I think that apart from possible discomfort, I’ll look funny running with them. However, the sun bothers me- what kind of sunglasses should I be looking for and how do they differ from ‘fashion’ sunglasses? Could you recommend some brand names, that won’t cost me an arm and a leg? Preferably international brand names or ones that I can purchase online.

if theye stunner shades then yes you need a new more fit to your face pair. Oakleys are good, gargoyles and ray bans you can try ebay for cheap payers some malls have cheap sunglass places