Being winter, I know there's a lot of TT owners out there busting their front bumpers on chunks of ice/snow in the road or from running off road to make up for people's dumb mistakes in the snow. Fortunately there are options and upgrades to those with messed up bumpers.
If you cracked just the lower portion, you can cover it up with a Votex front lip. Votex is OEM styling from Audi...which means OEM look, OEM fitment and OEM quality. They make rather clean side skirts and a rear valence too...you can find them on www.genuinevwaudiparts.com. If I recall, the front lip is ~$400. It can also be ordered from the dealership.
Pics of the lip:
No other lip gets the job done better/cheaper that I know of.
Other options include the OEM bumper ($400 from the dealer) the S-Line bumper (somewhere around $1200 from the dealer) or you can splurge on an aftermarket option.
For those of you who want to shave your alien doors, there's a version of the bumper without doors for headlight washers, the part number is 8N0 807 101 AA.