its an interesting catch-22. you can get work authorization by being sponsored by a company (and in turn work for them), but some require the authorization first before they look at your portfolio.
get a company to sponsor your H1-B visa, and jump over the pond.
you can be sponsored by a company via H1B, a very very competitive visa as there are quotas for this.
another way is an O-1 visa, or visa for aliens w/ extraordinary ability. you have to have had significant achievements for it, or at least, have very well established yourself in your field. this, i believe, has quotas as well.
you can also go to school in the US w/ a student visa, after which you will be given a year to work in the US using your degree. while working, it is up to your employer if they are willing to sponsor you or not.
So it’s possible to get an 0-1 visa before you have a job? Where do you apply? The thing that concerns me is companies want me to already hold a visa prior to applying.
i believe you can. you have to compile a portfolio of significant achievements, of work, awards, grades, your cv, etc…
for example, i know someone who was recognized by president bill clinton, got an emmy, worked for prominent hollywood and animation studios and got awarded the visa. i also know someone, a sweater designer, who got the visa too. she’s worked with some of the top fashion manufacturers and has been recognized with certain awards and such.