Aftermarket Accessory Suggestions

[Sabotage]

Hi everyone new to the forum,
I'm currently deployed in Iraq and finishing up my tour, I've ordered a 135i as a gift to myself set to be delievered upon my return to the states in December.
I realize this has been covered in a few topics but I still haven't been able to get a definative answer.

I opted against the bluetooth and BMW GPS, after test driving one while I was home on leave. Absolutely loved the car, but it didn't seem worth the almost 3k cost for the outdated GPS. Has anyone found or succesfully installed a touch screen or GPS/Stereo/Ipod integration into their 135i. I've read the threads about the warranties not being hurt by having aftermarkets installed, and I'm just wondering about if people have had custom shops install them, major electronic shops (best buy, ect.), BMW dealer itself, or personal install? And if having one in particular is better for the warranty? Also total cost from purchase and install as well as reccommended products?
I thank everyone in advance for your help/input. I've really enjoyed the forum so far, its answered a lot of my questions, and am extremely excited about not only returning to the USA after 15 months, but to drive my new baby.