vim and NERD Tree extension - adding a file

Activate the NERDTree and navigate to the directory in which the new file should live. Then press m to bring up the NERDTree Filesystem Menu and choose a for "add child node". Then simply enter the file's (or directory's name) and you're done.

From vim you can run shell commands. So in this case I use:

:!touch somefile.txt

and then hit r to reload the nerdtree window.

The other thing to do is to just start the new file from within vim.

:e somefile.txt

One handy thing for this is that in my .vimrc I auto change the cwd to the directory my current file is in:

" Auto change the directory to the current file I'm working on

autocmd BufEnter * lcd %:p:h 

This way if I'm editing a file and want another one in the same place the path is changed right there. Opening any file from NERDTree sets the directory to the one that file is in.