I got it working!

For anyone with the same problems, here is how I did it running fremantle 1.3.

It's probably not necessary but I did a factory reset of the phone.

I installed rootsh and leafpad through app manager.
Open X terminal and type sudo gainroot.
when getting root type: "cd /etc/apt/"
type "leafpad sources.list"
leafpad will open and sources.list will by default be blank.
in the opened document type in: "deb http://repository.maemo.org/extras-devel/ fremantle-1.3 free non-free"
make sure you don't write a capital D as in "Deb". It should say "deb"
save the file
go to x terminal again and as root type: "apt-get update"
let it update and it should take a minute or two.
after that type in: "apt-get install git-core"

That should do the trick