Thanks to everyone who has helped me improve the information on this page.
I haven't really found much information about Vitus online. I know they are an old company. Vitus is a well known maker of bicycle tubing. Acording to Sheldon Brown, Vitus is “France's leading manufacturer of high-quality frame tubing.” Many early aluminum bicycles used Vitus tubing. The frames labeled as Vitus were made and assembled by the French aerospace company TVT. Vitus made early carbon fiber bikes using the same designs as their high end aluminum bikes. They have not sold to the US since the early '90s. The last few years that Vitus frames sold in the US, they were only available through one of the major mail order companies. Vitus bicycles were available in Canada in the late '90s. They then disappeared from the internet for a while. In spring 2005, Nashbar had new old stock Vitus 979 frames for sale. Vitus now has an english website. Vitus is currently a house brand for Chain Reaction Cycles, a bike store in the UK (which for some reason has a .com address). Based on the information on their website, Chain Reaction Cycles has reasonable shipping rates to the USA.
I have heard rumors of trouble with the bonds on the ‘glued’ Vitus frames, but I only know of one example of problems with the bonding. The reader who had one of the joints come loose says that Vitus fixed it for him, though he had to pay the shipping. I do have many reports of bonded Vitus frames holding up over the years.