Woo! Someone who has an identical background as I do! I can't help you very much as far as your RAship, but I would highly, highly suggest applying to scholarships and attending a field school...although I didn't have one coming into my current Masters program, not going to lie, there are moments where I feel like a fish-out-of-water because I know nothing of field work. I've had to work a bit harder and study a bit harder in regards to my assistantship, but I've also been told by professors that I'm learning and taking away a lot more than the others who seem a bit "comfortable" with where they're at ...
Are you applying to grad school and you're just looking for experience in between now and then? Sorry, a bit confused.