Never mind that former New York mayor Rudy Giuliani is biding his time on "officially" joining the 2008 presidential throng, a number of prominent Houstonians are moving ahead with fundraising efforts on his behalf.The unannounced Republican candidate, a partner in Houston's Bracewell & Giuliani law firm, steps out at a $2,100 per person cocktail reception at the Houstonian Thursday night. And for those who reach very deep into their pockets — $30,000 deep — a private dinner with Giuliani will follow. This will be the first major dining for dollars event for Giuliani outside of New York.Among those already committing...