I'd already learned slapout-style breakfalls as a beginner in kenpo karate before starting aikido, so ukemi was an improvement. We start every class by doing lots of ukemi rolls forward all around the dojo, then backwards, and our Sensei helps anyone who needs help. People who've already learned it reassure newbies that you really don't get as dizzy once you learn it.
I take class 3x/week, which was enough practice that I got passably good at it quickly. As soon as we know enough so we won't get hurt, Sensei starts us with techniques where we'll have to take ukemi as uke (pairing beginner uke with experienced nage so we're less likely to get hurt).
I agree with Suzanne -- I LOVE ukemi!
I often work with a teen my size who
loves it, too; we jump up grinning like idiots after we've been sent flying, ready for more.