This is the website you need for visa questions
http://www.ukvisas.gov.uk/

Ok so Imis-read the working without a visa issue question.

Its much tougher to find work without a visa, cause you can't get a National Issurance number (similar to social sec) without one if you're a foreign national. Having no visa would mean, like the US, you have to find an employee who will pay you cash in hand, no questions asked. Thats going to be tough here as London is reet expensive so its going to be hard to make ends meet that way. As you'd expect the good messenger companies don't employ folks on that basis.

The other option is obviously for one of you to get a job where they will sponsor your visa (its a much less demanding process than in the US). Then you can both be here legally AFAIK.

TechOne probably has the best answer to your questions so I'm just filling in, until he shows up