okay you two... under the contacts / view section there is a drop down arrow that lets you decide whom to choose.
For me i have:
Google...
My contacts
Friends
Family
Co Workers
Android
Battleknight.
I personally dont talk to most battleknight and android users due to the fact they are already in my normal contacts. So i unchecked them. Co workers, family and friends why double them up. All i have checked is my contacts.
Once done go to your menu, settings, accounts and sync. Hit sync all. It may be a few i have google, tmo and weather. I do not like facebook or any other social update of my personal life so i dont care to have those. Now in my contacts i only have 76 people as before when i was in the same spot as you i had over 300. I hated the fact i had to have 5 phone numbers that are exactly the same for my dad and others taking up space.
Another thing you can do is log into t-mobile and delete your contacts. Also do the same on your sim card. I dont think there is a reason to have 3 different places to back them up especially when everyone is in the google section unless your paranoid.
Hope this helps.