How much does it cost to replace the front glass in an iphone 4?

I have a white iPhone 4 and I have 2 more years left with it due to my phone contract. I scratched it up and am looking to go to the Apple store to have the front and back replaced, but how much does it cost? I've replaced the BACK of my first iphone 4 through them before, and in Canada it was only $29.99 (the fee was later waived because it turned out the glass on the camera was defective which is why I wanted to replace the back in the first place).
Does anyone know how much the front costs? I'm assuming it will be over $100 as they have to replace the screen and everything. I know you can do it yourself by buying the part and tools online for a little cheaper, but I don't know if I would be able to take it apart and put it back together correctly.

$199 at apple

Go on amazon.com they can't be much because I had to fix the screen on my iPod and it cost 4 dollars for the screen then you can bring it to the store that way it costs less and they will put it on. I did this a year ago and it cost me 50 dollars I don't know how much it is now