EXS 24 Logic Sampler Users Group

Hans, you may want to check out Loop Editor:
http://www.audiofile-engineering.com/loopeditorplus/index.php
The download is working unlicensed as well (I'm almost sure at least, 
haven't tried the new "Plus" version yet), licensing it allows for further 
features to be used.

In case one needs more sophisticated features, Redmaticas "Keymap" is 
defenitely where it's at.

Regards
Sascha