Here's our roundup of the week's genealogy news:

• Thinking about registering for the National Genealogical Society Family History Conference in Raleigh, NC, May 13 to 16? Think fast: The early-bird registration deadline ends next Tuesday, March 31. Make the deadline to save $35.

• Not sure what to make of Twitter, Facebook, Geni, message boards and blogs? Genealogical Publishing Co. just released a book you might like: Social Networking for Genealogists by Drew Smith (one of the "guys" of the Genealogy Guys Podcast).

• It moved around a bit, but NBC’s "Who Do You Think You Are?" premiere looks to be set for April 20.

• With help from actor Richard Dreyfuss, the Civil War Preservation Trust (CWPT) announced this year’s list of the 10 Most Endangered Civil War Battlefields—Gettysburg, Pa., Cedar Creek, Va., and Spring Hill, Tenn., all made the unfortunate cut.

Want to help? You can start by helping spruce up battlefields on CWPT’s Park Day April 4.

• The National Archives Genealogy Fair is April 22-23. It offers classes on getting started, using online databases and records at the archives. There’ll also be exhibitors including Ancestry.com, the Library of Congress and the National Genealogical Society. See the National Archive Web site for times, locations, etc.

When the Stadtarchiv Köln—or City Archive of Cologne—collapsed Tuesday afternoon, two people died, surrounding buildings were irretrievably damaged, and more than a thousand years of records were buried in the rubble.

The archive contained 65,000 documents, the oldest coming from the year 922. The archive's holdings—more than 16 miles of files—included tens of thousands of maps, photos, posters and one-of-a-kind artifacts from the Middle Ages. The collection was valued at $500 million, according to Welt.

The city archive, which first found a place in Cologne city hall in 1406, withstood World War II with no losses. Officials say the building fell into a crater created by work on a nearby subway line. The building that collapsed was built in 1971. According to Wikipedia, it was built with an estimated service life of only 30 years. The archive reached its holding capacity in 1996; some material has been removed for storage elsewhere.

While emergency workers attempted to stabilize the building with concrete, about 100 volunteers have pitched in to save valuable documents from the rubble since Tuesday night, according to a city press release. A small portion of the archives was in an unharmed area of the building. Rain is expected over the next few days, so a temporary roof will be set up over the collapse site to attempt to save more documents.

Hamburg genealogist Andrea Bentschneider did research at the Cologne archive once and describes its holdings as "gigantic."

The collapse comes at an especially bad time, she says, because German privacy law recently changed to allow easier access to civil records. The city archive of Cologne had announced that as of this month, all death records up to 1978, marriage records before 1928 and birth records before 1898 would be available for research without restriction.

"We can only hope that these civil records as well as all other records were secured and saved on microfilm or a similar medium. Otherwise 1,000 years of Cologne's history may be lost forever," Bentschneider says.

It seems that much of the archive's content may be safe. Welt reports that former city archive head says a large part of the archive’s pre-1945 files were microfilmed; the backups are stored in the Barbarastollen archive in the Black Forest.

And FamilySearch filmed 171 rolls of film from the Cologne archive in 1984, says public affairs manager Paul Nauta. The library has been able to help other archives before by providing copies of the lost documents. FamilySearch’s holdings include these items from the Cologne archive:

• Genealogy and coast of arms 1350-1880
• Tax lists 1487-1703
• Orphans house registers 1592-1788
• Soldier pay records 1552-1613
• Court records, inheritance and land 1220-1798
• Court minutes 1413-1652
• Town council minutes 1440-1653

"This is one of the clarion calls for why preservation services offered by FamilySearch and other like organizations can be so critical. Most genealogy consumers are aware of the convenient access value, but the tragedy of the Cologne archive reiterates the value for preservation," Nauta says.

The Civil War Preservation Trust (CWPT), a group that preserves Civil War battlefields from encroaching development, did some math and announced its 2007 stats.

Last year, CWPT secured the permanent protection of 1,616 acres at 12 battlefields in five states: Mississippi, North Carolina, Tennessee, Virginia and West Virginia

One of those site is the Glendale battlefield (also called Frazier's Farm) in Henrico County, Va., where three Confederate divisions converged the retreating Union Army June 30, 1862.

An estimated 75 percent of Glendale's core fighting area is now preserved, at a price of $4.1 million. CWPT works by purchasing acreage or conservation easements (legally enforceable preservation agreements with landowners).

CWPT's 2007 totals pushed it past the 25,000 milestone: Over two decades, the group has protected 25,289 acres of battlefields at 99 sites in 18 states.

On tap so far for 2008: Passage of the Civil War Battlefield Preservation Program, which reauthorizes government funding for matching grants to preserve Civil War battlefields.