Below are some links that will help you with your family history research, and provide you with more information about Royal family trees.
British Family History - http://www.British-Family-History.co.uk/
If you've ever wondered who your ancestors were, how they lived their lives, and want to find out, then this is the website you should visit first. It will tell you everything you need to know about genealogy so you can begin to research your family history.
S&N Genealogy Supplies - http://www.GenealogySupplies.com/
The largest UK genealogy publisher and retailer. S&N Genealogy is a family-run business set in Wiltshire. This website sells all of the products in their catalogue (you can order a free catalogue - click here) and offers advice and customer feedback.
The Genealogist - http://www.TheGenealogist.co.uk/
Also maintained by S&N Genealogy Supplies, this is a vast online research site, where you can search census transcripts and indexes, BMD records, parish records, directories, navy/crew lists, and more. Their all-inclusive subscriptions are excellent value for money, and they also offer a Pay-as-you-Go service. They also offer a 30-day free trial.
RootsUK - http://www.RootsUK.com/
This is an easy-to-use site that lets you research your family history for as little as £5. As it is a Pay-as-you-Go site, you only pay for what you need - this is a great site for beginners. They also offer a free search - simply go to the site and enter the forename and surname of the person you're looking for, and click search.
The Official Website of the British Monarchy - http://www.royal.gov.uk/
This web site provides information on the work of The Queen in modern society, biographies of the Royal Family, a history of kings and queens through the ages, background on Royal residences and art collections, and coverage of recent Royal events.