How do i access ALL the blue tooth and handsfree features that come with this unit thru an IPHONE 3GS (4)? please direct me to a website that will inlcude tutorial and software driver downloads if I need them. Tank you

You will be able to handle phone calls (answer, reject, hold, etc), and import up to 100 numbers from your phone's contacts database. First of all, you must pair them with each other. Go to 'Menu > Settings > Phone tab > Connect > [New Device]'. Your device is in paring mode now. Then, make your phone's bluetooth application search for new devices. After a little while, KW-NT1 should appear on the phone' screen. Select it and make it connect. If a pairing code (or PIN, or passkey) is requested, enter '0000' (four zeros). If the pairing process is successful, you should see 'Connected' on your Car GPS receiver. Press 'OK' to confirm the operation. They are paired now. You will be able pair other 4 phones with this car GPS receiver (but connect only one of them at a given time). Now to import some of your phone's contacts database, from any screen, press DISP. When the AV bar appears, press the bluetooth icon, then 'Call Menu > Phone Book > Add', and see your phone screen for the selection of the number you want to import. For each additional number, repear from the 'Add' button. When you are done, press 'Finish'.
You will be able to make calls by dialling a new number, by going to 'DISP > bluetooth icon'. To dial from the call history or the stored phone book entries, press 'Call Menu'.
These are the basic functions. For additional resources on this car GPS receiver's bluetooth implementation, please, take a look at its user guide, from pages #77 to #84. You can download it from this location.
Please, let me know if I can assist you any further.
Regards, Carlos