Which LaTeX IDE has Vi plugin?

Kile has vim mode, as it uses kate as the editing component. It can be set under Settings/Editing/Editor/Vi input mode.

It does not support all vim features, but I found it good enough for what I needed (i.e. usual way to type/search/copy/move/...)

Here's how I installed the vim latex-suite on Ubuntu:

sudo apt-get install vim-latexsuite

sudo vim-addons -w install latex-suite