These are the new T-Mobile G1 cases of Amazon.com. Somebody knew how to please the G1 owners giving everything it needed: Color!
These snap-on solid G1 cases cost from 7 to 15 bucks, which I believe to be a good price.
Check it, if it does not look great on your G1, just return it, it’s Amazon!

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T-Mobile G1 Leather Carrying Case

High-end leather G1 Cases are being being sold at Amazon.com. These cases are made of high-quality leather and will surely make your G1 look elegant. This G1 Accessory is sold at a reasonable price taking in account the price of similar accessories for iPhone. Get a free Amazon Prime account to get this G1 case [...]

T-Mobile G1 (Full Body) Skin Zagg has just released its
T-Mobile G1 protective skin for the new phone. The same company that created the iPod’s InvisibleSkin is now producting the same superior quality product for the T-Mobile G1. Check it out! (Link)

These are Generic Cases that can be found at Amazon. Take a look on this one
Vertical Generic T-Mobile G1 Case:

NEW Google Phone G1 Android Leather Carrying & Protection Case (Perfect Fit)
That is the cheapest case for the T-Mobile G1 Phone that you’ll to find. If it’s a matter of protecting your G1 you should buy this case. To be a complete bargain, get it with free shipping by trying Amazon Prime.

This is the Case that Amazon.com is selling for the new T-Mobile G1 Phone. Nice G1 Accessory.

This is one of the many G1 Cases we review on this website. It is already available at Amazon. Check the reviews at Coolors.com Avoid scratching your new phone when it arrives!
Get it with free 2-day shipping with Amazon Prime: