I just completed my in-car solution...but it was not cheap.
- ProClip Padded Tilt & Swivel Mounting System - $75
- Kensington LiquidAUX for iPhone - $49
- Plantronics Discovery 925 Bluetooth Headset - $77
I got the ProClip because I wanted a solid, sturdy mount and all the research I did suggested this mount was top of the line. I'm not disappointed...this is a great clip, if a bit pricey. I bought this directly from ProClipUSA.com.
I got the Kensington LiquidAUX because I wanted to be able to charge my iPhone and send the music simultaneously through one cord...and it works great. It utilizes the iPhone's line out mechanism and sounds terrific on my car stereo (music goes from the dock cable and then into the charger, then up from the charger via a built-in 3.5 mm audio cable into my aux-in port). Got this from Amazon for $49 even though it retails for $80.
Lastly, I picked up the Plantronics headset because I wanted a way to operate my phone in my car without either getting a ticket or having to fumble around removing the iPhone from the mount in order to answer calls. I'm not a fan of Bluetooth headsets, but this one is terrific. It retails for $150 but I got it from Newegg for $77.
As you can see, it was expensive. But I got all top quality gear for this in-car solution and together they have been performing perfectly.