Up to 90 days for tourism and business purposes.
yes
No, US citizens cannot work in the UK without a visa.
No need for a visa, as the UK is a participant in the Visa Waiver Program.
In the way of actual paperwork, none apart from the marriage license. The UK citizen comes in on a visa waiver and you can get married in the US. For the US citizen to get to the UK, that is where the paperwork comes in. You both need to go to the UK embassy in the US and apply for a marriage visa for the US citizen to come into the UK. The US spouse will then be able to work straight away when you get to the UK also based on that visa.
Absolutely no! You have to obtain UK visa before going to UK
If you are not a citizen of the US or Canada, you must have a US Visa to travel in the US.
No, US citizens do not need a transit visa for the UK if they are passing through the country on their way to another destination.
Yes, US citizens need a visa to travel to the UK for tourism or business purposes.
Yes, the British citizen comes over on visa waiver. You can get married. If you both plan to then go to the UK straight after, you will then need to apply for a spouse visa for the US citzen at the UK/British Embassy in the US. This will allow the US spouse to come to the UK and also work straightaway.
The tourist visa is for a set time frame. You could get married, but the person would have to return home until they can get a residency visa.
You dont need a visa. Its part of the Visa Waiver program between US and UK
Yes, a UK citizen can work in the US with the appropriate visa or work authorization.