Oh dear - sack the 'local legal aid advisor' there is no probationary period of 6 months for a spouse visa during which the spouse cannot work. This applies only to fiancés who come here on a 6 month visa, during which they cannot work, after they marry they switch to leave as spouse during which they can work.
Your wife, if successful, she will be given a visa for 27 months, and will need to complete two years of this after entry into the UK before qualifying for ILR (as the rules currently stand). She will be able to work as soon as she arrives
As the rules stand currently, you need to show that you have at least the amount a couple on income support would have after you have paid rent and council tax - income support for a couple is currently £105.95 per week/£459 a month. You can show this either by savings to cover the two year period, and/or your income from employment or student stipend/etc if you recieve one. If you wife has an offer of employment or can show that she is easily employable (for example, she has particular qualifications) this can also be relied upon. If all else fails, you may be able to rely on 3rd party support.
The process varies from embassy to embassy, and depending on time of year. US applicants will probably find the process quicker than applicants from developing countries. You can find the processing times for the US here.
http://www.ukba.homeoffice.gov.uk/count ... angname=UK English