Well now we can tell you just the place to go if that's the case. Novikov in Green Park (just behind the tube) is both an Asian and Italian restaurant (on two different floors, not a fusion) that offers the long little leggies on their menu.
If you have never tried the dish before then this is likely a good place to get started. The frogs legs come as a starter option and are breadcrumbed and served with a garnish of chilli's and spring onions in true Asian style.
The taste is good, as most say - similar to chicken but we would suggest you don't look at the shape too much or try to pick them up as you would a chicken leg, by the bone as they kind of flop, like a frogs leg would we suppose, as it's a little off putting.
But there you have it, when you next wake up and wonder where you can go to get your London frog leg fix - you'll know just the place.