Adding Only Untracked Files

git ls-files -o --exclude-standard gives untracked files, so you can do something like below ( or add an alias to it):

git add $(git ls-files -o --exclude-standard)

It's easy with git add -i. Type a (for "add untracked"), then * (for "all"), then q (to quit) and you're done.

To do it with a single command: echo -e "a\n*\nq\n"|git add -i

Not exactly what you're looking for, but I've found this quite helpful:

git add -AN

Will add all files to the index, but without their content. Files that were untracked now behave as if they were tracked. Their content will be displayed in git diff, and you can add then interactively with git add -p.