According to hoopshype the Bulls are bringing in Hassan Adams, Maurice Ager, Quincy Douby, and Shawne Williams today.

I think it's really interesting that Paxson brought in Williams with this group of guards. He's the youngest of them by far, but he also has the most potential (according to most draft sites anyway). But he's 6-9 and played anywhere from the 2 - 4 slots for Memphis last year in a swingman laden system, and has been projected (again by most draft sites) to play the 3 in the pros. But if Paxson feels he could be the M2GwcDaS, how nice would it be to have a 6-9 guy to throw at Lebron and Wade... could be like having Prince actually if he could grow deffensively.  

here's Williams' nbadraft.net profile (draftexpress doesn't have one for him yet that I could find anyway):
http://www.nbadraft.net/profiles/shawnewilliams.asp