UPDATE 3 (April 21, 4:25 p.m.)
Sichuan Quake Relief returned earlier today from an initial needs-assessment and aid-delivery trip to Longbao Town in Qinghai Province. Click here to read more about it and specific details on what aid is still needed.
UPDATE 2 (April 15, 1:20 p.m.)
From Sichuan Quake Relief: Sichuan Quake Relief is sending a team from Chengdu to work with the Yushu Prefecture government and locally based NGO Plateau Perspectives to carry out wider needs assessments and help coordinate NGO relief activity.
The Yushu Prefecture government has requested aid in the form of medical personnel, medical supplies, and temporary shelters (tents and blankets). There is already a solid network of medical personnel in China prepared to depart for Yushu, and gifts of cash are the easiest and quickest way that you can help out. Gifts of supplies are more difficult and time-consuming to receive, and most supplies needed can be bought in the provincial capital, Xining.
Donations can be made here (please mark them "Yushu").
UPDATE 1 (April 14)
The China Siyuan Charity Foundation (中华思源工程扶贫基金会) has set up a website specifically to take credit-card and bank-card donations for the Qinghai earthquake relief efforts.
It's not immediately clear how the money collected will be transferred to quake victims, or via which organizations.
The Siyuan Charity Foundation was established in December 2005.
Over 20 million yuan was raised after the Wenchuan quake through such "third-party" fundraising methods.
Red Cross of China
Information to make donations to the Red Cross of China is here (in Chinese; translated below):
Account Holder: China Red Cross Society
Bank Branch: China Commercial Bank, Beijing Branch, Dongsinan Sub-branch
Account Number: 0200001009014413252
Foreign Currency Donations
Bank Branch: China Citic Bank, Jiuxian Qiao Sub-branch
Account Number: 7112111482600000209
Donations by Mail
China Red Cross Society
Address: No. 8 Beixin Qiao Santiao, Dongcheng District, Beijing
Post Code: 100007
Click here for the Red Cross Society of China website in English
Send the message "中国红十字会" (Zhongguo Hong Shizi Hui) to 12114 to access information including the Red Cross address, phone number, donations account information, or to leave your questions or comments.
Send the message "XX省红十字会" (replace the XX with the name of your province, for instance, "四川省红十字会"/Sichuan Sheng Hong Shizi Hui) to 12114 to receive addresses, phone number, bank information, etc. for local Red Cross Societies in any province, city, or district.
The Huffington Post has also compiled a list of organizations that are working locally or prepared to leave for the area.
Updates will be added as information becomes available.