Recommend a simple midi editor!
 

I have a midi song that I want crop the first half of. The 2nd half of the midi song is just a loop of the first half. Can anyone recommend a good program to do this?

I used to mess around with midi using a shareware program called noteworthy composer. It can import your midi file into a multi-stave sheet music format. You can change voices, add in notes (or compose from scratch), & definitely do what you want. If you can't find it on the web, PM me and I'll e-mail it to you.