Marcie, if you don't mind, how did you locate your travel agent or contact in China, and how do you judge their reliability? Anything you can offer or suggest would be a help. I have located several agents/agencies, and corresponded with one, but I’m not sure how to judge reliability.
Also, I have learned that the Chinese National Day holiday - October 1 to 3 - is a very heavy travel period in China, almost akin to our Thanksgiving weekend. Perhaps that's why Regent is not doing the Xian excursion from Beijing, but later from Shanghai, after the holiday period is over. The way you are doing it should avoid the peak period as well.

Lauri, I got the Xian excursion write-up from Ngaire, and I believe she got it from Regent. It clearly shows the tour as operating Shanghai - Xian - Hong Kong. The one I saw on the web site is for this year's (2006) tour they are apparently not offering in 2007. Here is a copy of the write-up I received:
Quote
RSSC
Programs for
Shanghai
China
Transport: Plane, Coach and Boat
Terracotta Warriors & Li River Cruise
SHA-P003
This optional tour must be pre-purchased, and is not included in the regular tour program. If you have not already pre-booked this optional shore excursion, please contact Regent Seven Seas Cruises Reservations at 1 (800) 285-1835 to verify the current status of this program. Limited space may be available, and should be booked via reservations. You may also check with the Travel Concierge Manager upon embarkation to verify if this tour is still available. RSSC reserves the right to withdraw this program if minimum participation requirements are not met.
A 100% cancellation penalty applies to overland programs cancelled within 60 days of departure.
Explore the spectacular ancient Terra-cotta Warriors and Horses, City Wall and the Big Goose Pagoda during a scenic visit to historic Xian, followed by an unforgettable picturesque cruise along Guilin's majestic Li River.
October 7, 2007 - Shanghai/Xian Depart from the pier to Shanghai Pudong Airport for your flight to Shanghai, then a connecting flight to Xian. Upon arrival in Xian, you'll be greeted by your guide, then transfer to a local restaurant for a delicious lunch. Afterward, you'll visit the Terra-cotta Warriors and Horses at the 150,000 square-foot Museum of Qui. In Pit No. 1, you'll see a truly remarkable sight; several thousand amazing life-size terra cotta warriors and horses created after Duke Xian's ascended to the throne of the State of Qin in 384 B.C. These amazing figures are displayed in battle order, rank by rank, with some mounted on horse-drawn chariots, others in infantry groups armed with spears, swords and crossbows. For centuries, the famous terra-cotta warriors guarded the tomb of Qin Shihuang Di, first emperor of a united Chinese people.
At the conclusion of your visit, you'll check in at the Sofitel Hotel - Xian, then transfer to the Tang Dynasty Theater Restaurant for a truly memorable dinner show. Afterward, enjoy an overnight stay at the hotel.
October 8, 2007 - Xian/Guilin Enjoy breakfast at the hotel, then depart for a visit to the City Wall and Big Goose Pagoda Built in 589 A.D., the Big Goose is one of the most famous Buddhist pagodas in China. After lunch at the airport restaurant, you'll fly from Xian to Guilin. South China's magical City of Guilin is home to some of the world's most awe-inspiring natural beauty. Situated in the NE Guangxi Zhuang Region, Guilin features verdant mountains, inviting waters, magnificent crags, and fantastic caverns. Upon arrival in Guilin, you'll meet your guide and transfer for check-in at the Sheraton Hotel - Guilin. You'll spend the rest of the day at leisure, then enjoy a delicious Western-style buffet dinner and an overnight stay at the hotel.
October 9, 2007 - Guilin/Hong Kong Following breakfast at the hotel, you'll depart for the drive to the picturesque Li Jiang, or Li River, which begins in Guilin and winds its way through the mountains and villages. Relax and enjoy a scenic cruise along the river, then visit Elephant Trunk Hill Park before driving back to the Guilin Airport for an early-evening flight to Hong Kong. Upon arrival in Hong Kong, you'll transfer to the ship.
Please note: An individual visa for China is needed for this program. Flights are based on current schedules, and may be subject to change. The order of sites visited may vary to avoid crowds and congestion.
Included: × Coach class air tickets Shanghai/Xian/Guilin/Hong Kong.
× 1 night at the Sofitel Hotel - Xian × 1 night at the Sheraton Hotel - Guilin.
× All lunches and dinners as noted in the itinerary. Local beer, wine and soft drinks to accompany lunch and dinner where included.
× Tang Dynasty dinner in Xian.
× All transfers and sightseeing as per program.
Not Included: All meals and drinks not specified above. Gratuities to drivers and tour director. Gratuities, laundry, telephone calls, cancellation insurance, and other personal items.
Availability and prices of tours are subject to change.

[size=8]Too Many To List - 416� days & counting on Radisson/Regent, and 150+� days on 8 other lines, with one cruise booked next month on the Mariner, Miami to Honolulu 22 days