It is very hard to do, aswell as very time consuming.
I had a sponsor for an H1-B1 visa, which would have allowed me to work legally for up to 6 years.
We hired an attorney to do all the paperwork. We didn't try and go through the pilot route, that was secondary.
We applied in April, but were told that all the H1's had been taken, so we should apply again in October, for the following April. If we were successful, then the visa would be issued the following October. They only issue 65,000 visas.
In the meanwhile we applied for a 'B' visa, which allowed me to work in the US for a set amount of time, but I had to be paid in the UK.
All in all it was a very frustrating thing to try and do.
The only up shot was that while over here I met a great woman (not like the ones that Mr. Sousa describes!). We took the plunge and spent a heap of cash on more paperwork, which we are still waiting to be completed.
I have to say that what Mr. Sousa desribes is very true. It would have been easier for me to go to Mexico and walk over! Heck they would even have given me a free driving licence.