Yea good luck, its a steam product.
It is rated gold but you usually have to do some config changes. This one notes that it wont run under fullscreen mode.
You can also try and strace the process to see what its actually doing although it will be probably be a bit cryptic. Try editing the config files for tf2 manually so it doesnt try to run in fullscreen and see if that helps.
I also didnt see 12.04 listed on the wine page so it may be an issue with either that version of ubuntu, the GUI you are using or any other number of variables.