After a two-month absence thanks to the prolonged writers' strike, the network late shows return tonight, Letterman and Ferguson with their full writing staffs and Leno, Conan, and Kimmel with only their wits and/or Kevin Eubanks (Letterman's independent production company Worldwide Pants cut a side deal with the Writers Guild for his show and Ferguson's). The writerless shows are expected to be handicapped not only by their lack of monologues and skits about masturbating bears but also by their inability to book decent guests thanks to celebrities' reluctance to cross picket lines. (And the WGA is reportedly planning to picket tapings of the three shows as well as The Daily Show and The Colbert Report, which return on Monday, also sans scribes.) Tonight on Letterman: the annoying but hugely famous Robin Williams. On the Tonight Show: Republican presidential hopeful Mike Huckabee, whose recent surge in popularity can, ironically, probably be attributed to late-night hosts' inability to mock him during the WGA strike. No word yet on whom other shows have booked, but since they're keeping quiet, one can only assume their guests are even crappier than Mike Huckabee.