[Note: This is an unfiltered list of sites that appear to be on-topic.No attempt has been made to confirm the information on these sites.]
The Subchasers of WWI, Theodore Treadwell.
This is a page of a larger site, Splinter Fleet: The Wooden Subchasers of World War II, a site with lots of good information about chasers. It offers a clear and quick introduction to the chasers in WWI, although the site as a whole (as the name suggests) focuses on the subchasers in WWII. Treadwell is author of the book, Splinter Fleet - The Wooden Subchasers of World War II.
A short overview of chasers in WWI and WWII, offering general information about the construction history, armament, and hull numbering system of chasers.
Submarine Chaser Photo Archive, NavSource Naval History Site (Joseph M. Radigan)
WWI and WWII suchaser photo list of various chasers. There are some nice shots.
[Note: see also the Hull Number Photos page of the Chasers section of this site.]
Mine-sweeping tale of high seas surfaces with trunk, reprint of an article in the Lakewood Sunday Post, June 23, 1994.
Short article about Charles E. Kyle's involvement with the building of chasers in 1917-1918
Index for Sub Chasers, Dictionary of American Naval Fighting Ships web site
Indicates manufacturer information and post-war sale information on chasers by hull number
Includes notes on several subchaser incidents.
[Subchaser.org Editor's Note: Mr. Franklyn K. Brown noted that the deck logs of the S.C. #95 indicate that the mine incident ocurred in August of 1919, not September 25, 1919 as this site suggests.]
History of Communications-Electronics in the United States Navy, Captain Linwood S. Howeth, USN (Retired), 1963, pages 297-312. Describes the early history of listening devices, including the listening devices developed during WWI.
Jeffrey Charles' site on the British ML boats, smaller precursors to the 110' U.S. chasers. These boats were built in the U.S. by Elco, the same ship builder that built SC 93, Lt. Dole's first command. Lots of good information and photos.
Accounts of Specific Subchasers and the men on them
Page on SC 110, with nice photos of a group of chasers and of SC 273.
Diary of Fred George Bankson, who served on SC 177 in the English Channel. Includes an account of the submarine attack in May, 1918 that Moffat describes in the book Maverick Navy.
Sites about the Otranto Barrage
This is the story of an Austrian attack on the barrage on May 15, 1917. It lists a number of the ships that took part, and provides a few low-res photos and illustrations.
The Otranto Barrage, FirstWorldWar.com web site, Michael Duffy, editor
One-pager on the barrage, critical of the claims of its success.
Sites about the Archangel Expedition
U.S. Participation in the Archangel Expedition, The World War I Document Archive. (attributed to Foreign Relations of the United States, 1918, Russia, Vol. II, p. 287 ff.)
A short document on the U.S. position on the expedition at the time. (Pre-dates the subchaser mission to Archangel)
The Archangel Expedition, Documents of World War I, Vincent Ferraro section of the Mount Holyoke College web site, (attributed to ß, 1918, Supplement on Russia, Vol. II, pp. 287-290.)
Another source on the U.S. position on support in northern Russia in 1918. (Also pre-dates the subchaser missions.)