This is my experience regarding the online Yizkor books; my special interest is in the Steibtz-Schwerznie book. When the individual article titles are in black, those items have yet to be translated and posted online. If the title appears in blue, that is an active link, and clicking on it should take you to the translated article.
As Max mentions in his response, it is possible to donate to the project of your choice, and request that priority be given to specified articles. To do this, contact the project coordinator for the book in which you are interested. The books contain articles in Yiddish and Hebrew, and it is necessary to coordinate with an appropriate translator. A few years back, I sponsored the translation of the Yiddish portion of the Schwerznie book; the translator I worked with at the time was unable to translate the Hebrew articles.