I went from nobody to shadow to four in a brief period, but it was all about connections. Two guys were surgical residents with my sister, but I was a little hesitant despite schools saying residents were suffice.
I then asked a friend who was an attending with an EM group at the hospital our aircraft primarily served. There were two DOs with their practice, but I had heard a lot of good things about one of the younger guys. He was really helpful to a lot of the medics from the FD that dropped patients off there, so I asked my friend to see if he was open to it. He got me his email, and told my friend it wasn't a problem. I emailed him my CV, told him about myself, and wanted to know if I could shadow and obtain a letter. I was upfront: I need to obtain a letter from a DO, but I want to have quality shadowing time too.
I didn't hear anything from him for awhile. I was at a PR event at the hospital one day, it was a BBQ put on by our company for EMS week. A lot of hospital staff came out to grab food and the other DO came out as well. I said "Hey Dr. X, my name is xyz and I am applying to DO school. I was wondering if..." He interrupted me and said "and you need a letter. Sure. Call the scheduler, find out what days I am working and show up for a shift." We chatted for another few minutes, he gave me the contact info, and then he went back inside the hospital. The scheduling lady never called me back, and I didn't want to just show up at the hospital and bombard him during a shift. I ran into him on a couple of flights where I transported a patient he was sending out, and he told me a couple of times "Call Y, tell her I said it's fine and just show up."
Then the other DO responded. I did about 50 hours with him and 12 with the other guy. The one I did 50 hours with said only 2-3 shifts would have been fine, but the school preferred at least 50 hours I think. Regardless, he wrote me an awesome letter. I had a lot of fun during my shifts though because we were able to talk about a lot of stuff that he sees, stuff I transport and how my experiences furthered my specific interests in medicine. We talked about a lot of stuff though, kids/family/healthcare/politics. The whole spectrum. He also helped teach me things that would improve my current practice as a medic, which is what I really enjoyed about it the time I spent shadowing. He, along with the other docs and PAs working the shifts, were all about giving me pointers for interviews.
I got a ton out of my shadowing time. I wrote a thank you letter to the medical director of the ED and mentioned everyone by name that helped make my shadowing experience so awesome. I got a really strong letter from the experience, but I took away a couple main points: they're really busy, and they look forward to repaying the favor that another DO did for them when they were applying. So capitalize on that. Be succinct and provide them with everything you can that demonstrates you are a mature and well rounded individual. I sent CV, academic information, and personal statement.
Good luck.