At the university level, many of our PhD's post fliers on campus looking for research assistants. Any of your upper division class prof's can give you a few names of prof's to ask. If you like the prof, I'd recommend getting into his/her lab... it makes things soooo much easier.
If you're looking for clinical research, start asking the people you're shadowing, or the physicians where you volunteer. I've actually ducked and avoided two such "opportunities"... if i were lacking research experience i would have gone for it 🙂
Above all, choose something you're at least remotely interested in... your interest will shine thru in the quality of your work.
I've fielded the "EMT" question from several of my students... personally I think that it's interesting, and i'm glad that i did it... but there's quite a bit of "wasted" time if you're just doing it for the way it will look on your resume. I can't imagine any advantage an EMT would have over anyone else with good clinical experience.
As for the CC credits... i agree with the above poster... and add that in this day and age of working and moving and bootstrapping your way towards a goal, sometimes a community college class (or two) is inevitable if you don't want to take the semester off. One would think that this situation is SO common, as to no longer be a big deal at all (if it ever was?). That being said, I would try to avoid any appearance of a "pattern" to your community college classes.... ie ducking out to take ochem or any of the other percieved "toughies."