EASTERN SAUDI ARABIA (AP) _ Two weeks into the war with Iraq, U.S. troops are still pouring into Saudi Arabia, bringing the American deployment closer to the 500,000-troop mark.

Some soldiers arrive on 747s that touch down daily. Other newcomers aren't so lucky. They spend their last hours in peace aboard noisy military transports.

For most, a bus awaits for a crowded ride several hours north, perhaps with a stop to hook up with a tank, a truck or a helicopter.

Military officials will give few details about the U.S. buildup, but it appears it is almost completed.

Many of the new arrivals are National Guard and reserves who will round out combat units, work in field hospitals and blood banks and keep supplies moving to troops at the front.

More than 20,000 have been called up since the war began two weeks ago, and they come from every state.

In all, 201,000 Guard and reserve members have been mobilized for the Persian Gulf deployment, including 141,290 by the Army, 22,141 by the Marines, 21,645 by the Air Force and 15,093 by the Navy. Fifteen percent of the troops in Operation Desert Storm are from reserve units.

The biggest group of new troops came from the Army's 7th Corps in Germany, which includes the 1st Armored Division, the 3rd Armored Division, the 2nd Armored Cavalry Regiment and a brigade-sized unit from the 2nd Armored Divison.

Saudi Arabia's major highways are lined with equipment for those troops, including tank transporters pulling M1 tanks, Bradley fighting vehicles and armored ammunition carriers.

The last ground forces to arrive may be among the first to fight. The units in Germany are among the Army's best trained and equipped.

All told, the units from Germany have about 1,000 M1-A1 main battle tanks, hundreds of Bradley fighting vehicles and a large number of AH-40 Apache attack helicopters and Hellfire anti-tank missiles.

These troops appear to be settling in after some quick desert training.

''It's slowing down now,'' said Sgt. 1st Class Enrique Trevino, who works at the 7th Corps weapons calibration range. ''Just about everybody has been through.''

Also new to the front is the 1st ''Big Red One'' Mechanized Infantry Division from Fort Riley in Kansas.

These forces joined up with the armor and other ground forces who came in the first wave of the buildup and now form a powerful line across the northern Saudi desert - from its border with the Persian Gulf just south of Kuwait to well past Kuwait's western border.

At the gulf edge of the deployment are the Marines, including members of the newly arrived 2nd Marine Division, which reached Saudi Arabia just a week before the war began.

There was little time to train, but that didn't seem to bother the Marines.

''You're never perfectly ready,'' said Lt. Col. Andy Mazzara, a battalion commander. ''But you have to remember - we didn't start out from scratch. We train all the time at Camp Lejeune. We have units that are constantly ready for contingency operations.''

At least the 2nd Marine Division had a week before war.

Pvt. Gregory White of Los Angeles is truly a new arrival - he got to Saudi Arabia after the war started.

Now here a week, the 20-year-old scout for the 82nd Airborne is within eyeshot of Iraqi troops and is a forward scourt for the division's 2nd Brigade.

With no time for extra training, White has a simple answer when asked how he'll protect himself so close to the enemy.

''I'm going to dig more and more until I can't dig no more,'' he said.