British Expats - How long can I stay in the US as a visitor?

Can anyone clarify if it's possible to stay longer than the 90 days allowed under the visa waiver scheme? I was under the impression that you could stay 90 days, leave the country, then come back in for a further 90 days, but that that would be the maximum permitted in any calendar year. I am however getting all sorts of conflicting information from everyone I have asked, and especially from US visa sites!! How does one acquire a 10 year tourist visa? My situation is that my partner has transferred here from the UK with his job and I would therefore obviously like to stay here for as long as he is here (possibly 1 or 1.5 years). Ideally I would like to work but understand that may be tricky, not having a job offer already.. Thanks in advance.