First, I can find lots of things about current students moving and studying in the UK, but not a lot for adults that are not current college students. How easy or not would it be to move to the UK with the intention of going to university full time if you're not a current college student?
Well, you have to get accepted onto a degree course and be issued with a student visa before you can come to the UK, but qualifying for a student visa isn't that hard.
Basically, you just need to decide which university and course you wish to study, apply for the course, get accepted and then apply for a student visa when the paperwork is sorted, and then move to the UK just before the course starts.
However, you do need A LOT of money available to you in order to get a visa (current college students doing study abroad years will usually have financial agreements in place with the university - I studied abroad in the US on an exchange programme during undergrad and the entire year only cost me $800 in tuition fees... it would have been $18,000 if I'd come as a regular international student).
You will need at least the first year of tuition available to you, which is about £15,000, plus 9 months worth of living costs, which is around £10,000 or so. You either need to have it in your bank account in full for 28 days before you apply for the visa, or you need to have an approved US loan in place.
Also, if you were to get a student visa and your husband wanted to join you in the UK as your dependant (or vice versa), you would need to be studying for a masters degree or higher. If you were an undergraduate, he wouldn't be able to qualify for a dependant visa and would need to qualify for a visa in his own right to live in the UK (either a student or work visa).
Second, the most daunting aspect is finding the funds for living and school. If I'm not a current student, can I even find scholarships/grants to help with the cost?
It may be possible, but I wouldn't bank on being able to qualify for any UK grants or scholarships, because most are only available to UK/EU citizens or permanent residents in the UK.
Unless you have large savings, you may well need to fund your studies through US loans (i.e. FAFSA, Sallie Mae or private loans).
Third, all of this considered, should I even to apply for a student visa? Or just start out working and establish residency first and eventually become a student?
You need a visa before you can come to the UK to either work or study - you can't just move here and then decide.
The easiest visa to get is a Tier 4 student visa as long as you have the funds and can get accepted onto a degree programme.
The most difficult visa to get is a Tier 2 Work visa, because unless you work in a a very highly skilled or in demand field, the UK company would have to prove that they have advertised the job across the UK and all 26 EU countries (that's 500 million people) and could not find a single suitable applicant before they can hire you.
See here for more information about student and work visas:
https://www.gov.uk/tier-4-general-visa/overviewhttps://www.gov.uk/tier-2-general/overview
