But it looks to me that you can only get H1B visa's which makes you totally dependent on a single employer without the ability to change jobs.
Do you have citizenship?
As the others pointed out, it is possible to transfer between jobs on an H1B. People do it here all the time.
The easiest way to get out here is to go through your university. Industry approaches postgrad students all the time to come work out here. I had Google, IBM and Microsoft, Sun, Intel and a few others all stop by my department, looking for candidates to relocate specifically to California. Failing that, it would be best to have a holiday over here and line up some interviews for while you're in the area.
I can't recommend it enough by the way.
AFAIK, You need to be careful about changing jobs though, if you are out of work for some amount of time (a month?) your visa expires on you.
You are correct that out-of-work is a very bad place to be as an H1B holder. But USCIS allows you to interview for a different job, apply for visa transfer to the new company and quit the old company after the visa transfer is approved.