Is there a special military unit that provides bodyguards for our generals in Iraq?
Are they GIs or contracted civilian budyguards?

Depends on what ya mean by "General"

I'd have a hard time believeing an ADC for logistics would get a detail.

That said, I do know lots of regular troopies are getting PSD training before deploying.

Quoted: Depends on what ya mean by "General"

I mean like when General Frank was there he always had couple of armed bodyguards around him.
I've seen other generals in Iraq on TV with budyguards around them.

During GW1 Norman Schwarzkopf had bodyguards with him when he flew in to accept the Iraqi surrender. They weren't wearing your everyday BDUs and looked like guys with some "age and experience" as opposed to your average enlisted soldiers in their teens and twenties. IIRC there was mention that they were part of a special security detail assigned as "bodyguards".

ETA www.findarticles.com/p/articles/mi_m0OXU/is_11_58/ai_111113832

I have about 30 clients who are General Officers, and about a dozen of whom work in the same palace where I do (including [4-star] GEN George Casey).  It’s not uncommon to see a one-banger moving unescorted or even driving himself (but I only see them in the secure compound).  Less common to see two-bangers without their military PSD guy.  LTGs and GENs rarely go to the crapper without their military body guard in tow.

When there’s big doin’s -- large gatherings, formal meetings and such -- the whole palace gets a really tense air and fills with keyed-up military and civilian PSD guys (Blackwater, Triple Canopy, etc.).  The generals’ PSD guys usually just carry a sidearm and don’t habitually even have a magazine inserted in it (‘condition green’).  When it’s ‘show time’, there’s “thumpers” everywhere with CARS and SMGs slung across their chests, magazines inserted and their strong hand on the grip, eyes in constant motion, checking everyone’s hands.

I see them every day but I can’t always be sure which are military and which are private.  Usually but not always.

A guy I work with is an Iranian who was an MP in 3rd ID during the invasion.  He worked a protective service detail (PSD) for LTG Blount during the 3rd ID's time in Iraq, carrying an MP-5, along with five other MPs.