I installed Cyanogenmod and noticed that Google Mail is missing. I can't install it form the Market either. Market, Talk and so on are there, just Google Mail is missing.
How can I install Google Mail?
There seems to be a problem with the latest Cyanogenmod 7.1.0 and the german locale. Possible solutions are
Google does not provide some apps in the Market, since they're intended for "approved" devices (ones that meet Google's compatibility guidelines). However, I believe they have a special agreement with CyanogenMod where you can flash the apps separately. You can read more about how to install these packages at "How can I install the Google Apps Package (Play Store, …) on my Android device?"
Install ROM Manager from the Market and then go to Download ROM, find Google Apps in the list and then you can choose the latest and install it. You can also see comments and ratings from other users.