I don't think its the coils... if you have a multimeter then there are some tests you can do, look on here Automotive Training and Resource Site
sorry I cannot remember what the readings should be but if you look long enough you will find them on autoshop.
I would suggest that it is the cam sensor that is at fault, you can find it on the back of the cylinder head, left side (oil filler cap side), one 8mm wrench and pull the plug will have it removed.
You will find that it is covered in gunk, probably from the cambelt!!, clean it first, check and see if it still has a magnetic pull and if you have a multimeter check it for resistence, I think I read that it should be 1000 ohms but check autoshop again.
I have heard of problems on other cars where the car starts when cold but refuses to start again when hot. The owners have removed the cam sensor and put it in the fridge and once cooled refitted it and the car starts, no idea why, do't ask me!
Also I believe that the motor needs the cam sensor to start but it is redundant after that, at least until the next time.