If you go into your account settings, you should see a thing about setting time parameters. I live in an Eastern time zone and I believe it is GMT - 5 hours. I have set it accordingly.
If you want to keep track of tournaments that you have already found and want to play in (without forgetting), use a calendar on your computer that has reminders, etc. I use one at work (MicroSoft Outlook) and at home I use the one tied to my Yahoo! mail account.
I hope this helps.