I'm currently looking for a flash diffuser for the Canon Macro Twin MT-24EX. I see that many people make their own. However, I'm not very good about building stuff. Is there anything available in the market? I haven't found much so far.
Stofen make a set of diffusers that fit the MT-24EX. Although they get good reviews on B&H, most photographers prefer to make their own, not because DIY is cheaper, but because DIY diffusers can provide more diffused lighting than the Stofens.
Puffer diffusers can also be used on the MT-24EX, though they don't clip in place. An elastic band will be needed to keep them on the heads (and even then they sometimes slip off).
As the others have said, it's really worth while making your own. Personally I use DIY concave diffusers or a vellum paper 'tent' diffuser.