SOLO (Search Oxford Libraries Online) is a good starting point to find books on US History.
Use author and/or title searches to find books:
author = carwardine + title = lincoln
Use subject searches if you don't know the title or author. Examples:
You won't find journal articles in SOLO Oxford Collections!
Key resources are listed below. Additional resources, esp. for tracing early printed material, are listed separately.
A good starting point: Bodleian Library's Theses page.
The Bodleian Library holds nearly all Oxford postgraduate theses in the humanities where a deposit requirement is stipulated by the University: all D.Phil. (doctoral) theses, all B.D. theses, all B.Litt/M.Litt. theses since Michaelmas Term 1953, and most B.Phil/M.Phil. theses since Michaelmas Term 1977. Theses on the United States are held at the VHL.
All new humanities theses since January 1994, and an increasing number of D.Phil. theses catalogued retrospectively, can be found on SOLO.
Many theses from other UK universities are available to be downloaded for free from the British Library's EThOS service. If you need assistance with a thesis which is not held in Oxford, please contact library staff.
The VHL has extensive collections of US government publications and official papers. See the separate US Government Publications guide for more detail and links to resources.
Key finding aids: