There was another thread on this topic back from November... feel free to search for that one. I'll give the simple version here:
H1B - pros: counts towards citizenship and don't have to leave the country for 2 years after training. The problem is: $$$, application fee alone is $1500 to the government and then there is lawyer fees, etc. I was told it cost about $5000 in total. Plus it's not guaranteed - much higher rejection rate than J1. And most likely won't get approved between match day and start of residency (even J1 has that risk but H1B is harder to get). Also, reading the definition of who qualifies for H1B, I'm not sure residents qualify for H1B just because it's still training (i.e. no permanent license, no specialty board certification)
J1 - much cheaper ($100 application fee + another fee once issued but overall cost is much less); resident's job definition meets the criteria for J1. Overall, much easier paperwork than H1B (but still a beast! Residency coordinator have to spend a solid 3-4 days per J1 app!)
The short answer is - no, I haven't heard of any program willing to sponsor H1B (not just EM but friends applying to any other specialty). It just doesn't make sense for the residency programs since it's more expensive and more hassle. As it is, there are many programs that don't even sponsor J1 just to save themselves the headache. If you find an exception though, please let us know.
