I've done some reseach into the next lens I'm going to buy. I've got a canon 1000D and the kit lens 18-55mm. I think the next lens I want is the canon 50mm 1.8. I've considered the 1.4 and yes it's probably a better lens but as I'm just starting out (don't how serious I'll get) I'm not sure I can justify the extra cost of the 1.4.

I've read most photographers have a 50mm lens but as I have a camera with a crop factor of 1.6 should I be looking at a lens of around 28mm to get the same affect as the 50mm?

I'm also considering getting a telephoto lens of some sort and looked at canon's 70-300mm f4 IS USM and their 70-200mm f4 L USM. The type of photography that I want to get into is sport/dance but I'm trying everything at the moment as it's just the start. I'm more unsure about choosing this type of lens because I don't want to regret within a year that I didn't spend the extra money for a better lens but I also don't want to spend a fortune if I don't end up making the most of it. Any advice on this as well would be greatly appreciated.

Jo