Just found a cool feature on CafePress: you can place your Google Analytics tracking code on your CafePress store. Sweet.
Found under "Your Account -> Manage Shop -> Update Tracking Information".

Also, new design - Chuck Norris shirts on Bitzwear.

Update: this wasn't clear enough - before typing in the tracking code in CafePress you should create a website profile for your shop, using the "Add Website Profile" in Google Analytics and typing in the shop's URL (e.g. www.cafepress.com/your_shop). Then paste in CafePress the code generated by Google Analytics.