To search for works on early Tokugawa Japan in English, use an Orbis keyword search with English set as a limit. (The 'Set Limits' tab is located to the lower right-hand side of the search box.) Try 'Japan history Tokugawa,' or 'Japan history' and a relevant date. For more examples, see Reiko Yoshimura's website.
In this period, Westerners steadily encountered Japanese through the Dutch outpost at Nagasaki. See Travel Accounts for suggestions and examples. Also refer to Professor Botsman's bibliography.
Created by Professor Dani Botsman, this bibliography contains dozens of Western accounts of travel to Japan, beginning in the 16th century. The sources are grouped chronologically, and are linked to their respective Orbis records.
The Historiographical Institute at the University of Tokyo offers a wealth of online resources: most of their databases are in Japanese, but the On-line Glossary of Japanese Historical Terms (located under 'Tools') allows you to search for terms in English, French, German and Japanese (romaji, hiragana, and/or kanji). The database returns works (in all these languages) that contain the relevant term, and also serves as a useful tool for translation. To search using a non-Japanese term, enter the term (or terms) and click the 全文検索 button; to search using a romanized term, click the 語彙検索 button.
For help with Japanese dates, refer to Tsuchihashi's chronological tables.
John Dower's Japanese History and Culture from Ancient to Modern Times: Seven Basic Bibliographies contains a chapter devoted to the historiography of ancient and pre-modern Japan, with some translated primary sources.