I've just put my Common Lisp Tcl/Tk bindings online. They differ from the existing LTK library in that they...
Support for both FFI bindings and talking to a
Have hardly any 'wrapper' functionality — you're directly driving a Tcl interpreter from Lisp.
They've only been used in one medium-sized project so far, but they are so simple that I'm rather confident they work as intended.
Project page at http://marijn.haverbeke.nl/cl-tk/.