I did exactly what you're doing a short time ago. Found a decent immigration lawyer, applied for my Permanent Residency in Nov '07 and was awarded a Green Card in May '08. Was offered a job with a Part 135 operation (NY) flying the Beech 400 and BE20 bt ultimately decided against it due to the nature of the work... Decided that flying in the US was strictly for the birds... crap pay, crap conditions... unless you're very lucky. Now am in aviation but not flying....
Would suggest that you have a minimum (minimum mind you) of $10,000 to spare before applying for the Green Card.... oh yes... and don't live in NY
Throughout my career I've lived, worked and visited over 70 countries inc all of the middle east, most of Africa, Afghanistan and parts of Russia... NY is as close to a police state I've ever had to suffer.