I try to install TF2 but it says i don't have enough space but, I have well over 50GB on my laptop, What's wrong and how do I fix it?
Look at output of:
You may have smaller size of /home partition. You can resize it through LiveCD and gParted on it. Boot LiveCD, select Try Ubuntu and launch gParted. You can modify partitions as you want/need.
Don´t forget to backup everything on it first.