I don't want to dampen your enthusiasm, but if you got to a 12th great grandparent in one day, you likely need to start over. The only way that could happen is if you copy every tree you come across, but the member trees are notoriously inaccurate (especially when they claim to go back that far), and I really doubt there is much if any documentation on any of them - just a general "trust me" approach.
You will have a lot more confidence in your results if you start from your own parents and grandparents, and work backwards one generation at a time, adding the census and other records along the way. The problem with just copying trees that have no records attached is that if there is any break in the chain, then you are not really connected to those older generations (or if you are, you will never be able to prove it to yourself). Also, if my own experience is anything to go by, you are also going to find situations that are chronologically impossible (parents younger than "children," spouses born 80 years apart, etc.)
As to crests, etc. - the real truth is that these are not "family" crests. If you read up on heraldry, you will find that there is no such thing as a "family crest" for any family (notwithstanding the colorful clipart littered over the Ancestry trees). You might have fun with a Google search on that subject.
Good luck with your search - but seriously, start with your own immediate family and work backwards, and you will then have a tree you can trust is really about your family.
Update: Here is an official source about UK coats of arms, which explains in more detail that there is no such thing as a "family" coat of arms - they are granted to individuals, and can be inherited only by lineal male descendants of the original grantee: http://www.college-of-arms.gov.uk/resources/faqs