Just checking to see how long and if possible to get a tourist visa to UK in relative ease for couple going for a week holiday from Thailand to UK Cheers!

You would not need a visa for the UK since you are a US citizen.

You wife will need to apply for one though. Have a look at this pinned topic for info.

 

It is relatively easy for a genuine visitor, tens of thousands of visitors are granted visas every year.

Your wife will need to satisfy the Entry Clearance Officer who decides on her application that her visit is genuine, affordable and that, on the balance of probabilities, she will leave the UK at the conclusion of her visit.
As Joe has pointed out you will not need a visa but you will need to satisfy the Border Force Officer on arrival at the UK Border  that you're also a genuine visitor, rarely a problem.

As well as the line to the pinned topic have a read of the application process vfsglobal/thailand

Have a read of Standard visitor visa from UKVI as well.

 

The most common difficulty British sponsors have is showing that their visitor, especially if they are a spouse or partner, will leave the UK at the end of their visit and are not attempting to use a visit visa to bypass the settlement rules.

 

As you are American and, presumably, not resident in the UK then you shouldn't have this problem.

 

If you live in Thailand provide evidence of your immigration status there, if you live in the US then provide evidence of your wife's immigration status there.

 

Processing times vary depending upon where you apply and how busy they are at the time. I recommend that you allow at least 15 working days for her application to be processed.