A big part of the preparation for UK based scholarships is narrowing down your choice of universities and programs. The following resources will help your research:
The Complete University Guide: http:/www./thecompleteuniversityguide.co.uk
The Guardian University Guide: http://www.guardian.co.uk/education/universityguide
The Education Guardian UK Research Assessment Guide: interactive
The Fulbright Program offers opportunities in all fields of graduate coursework, research or English language teaching in 140 countries. Grants are usually for one academic year and provide round-trip transportation, language courses (as appropriate), tuition and fees, living allowance and basic accident/health insurance. U.S. citizens who are graduating seniors, holds a B.S./B.A. degree, are master's or doctoral degree candidates or young professionals or artists are eligible.
The Gates Cambridge Scholarship provides funding (tuition, living allowance, research or conference expenses, and roundtrip airfare) to pursue either a second Bachelor's degree, one year of post-graduare course work or research leading to a Ph.D. in any field at Cambridge University in England. Students must be U.S. citizens with an outstanding academic and leadership record, strong supporting references and clear reasons how study at Cambridge will further their long-term academic and professional goals.
The Marshall Scholarship provides full funding (university fees, cost of living expenses, annual book grant, thesis grant, research and daily travel grants, RT airfare and, where applicable, a contribution towards the support of a dependent spouse) for 2 years (with a possible 3rd year extension) of graduate study at any British university or associated institutions. All academic fields are eligible. Candidates must be U.S. citizens and hold a Bachelor's Degree with a minimum GPA of 3.7 at the start of the grant period.
The Rhodes Scholarship provides full funding (tuition, living allowance, travel to and from Oxford) for 2 to 3 years of study at Oxford University in England. Scholars can pursue either a second Bachelor's Degree or a Graduate Degree. All academic fields are eligible, providing the course of study is available at Oxford. Graduating seniors or recent graduates who are U.S. citizens, ages 18-23 are eligible.
The Mitchell Scholarship provides full funding for one year of post-graduate study in any discipline at any university or associated institutions in Ireland and Northern Ireland. Candidates must be U.S. citizens between the ages of 18-29 and have a Bachelors' Degree by the start of the grant.http://www2.us-irelandalliance.org/content/3/en/George%20Mitchell%20Scholarship%20Program%20|%20US-Ireland%20Alliance.html
Scotland's Saltire Scholarships (SSS) is a substantial program of scholarships, offered on a matched funding basis between the Government and Scottish Higher Education Institutions. The scheme offers up to 200 awards, each worth £2000, towards the tuition fees of a one year Masters course at any of Scotland's higher education institutions.
The scholarships are designed to support the promotion of Scotland as a learning nation and a science nation and are therefore targeted at the priority sectors of creative industries, life sciences, technology, financial services and renewable and clean energy (find out what study options are available).
The Frank Huntington Beebe Fund provides fellowships to gifted young musicians, generally performers and composers in classical disciplines, to pursue advanced music study and performance abroad (usually in Europe). Fellowships are awarded to students at the outset of their professional lives and who have not spent an extended period of time abroad previously. The award is for one year and provides funding for round trip transportation, living and other expenses up to $22,000.