If you have already taken some Spanish in school, one thing I'd recommend is watching one of the Spanish soap operas. One colleague did this and said it really helped him--the actors speak good Spanish, clearly, and the visual cues are very helpful. If you watch the same onefrequently, you'll get to know the characters and story lines. Plus the cultural stuff is imbedded into the show, so you'll pick some of that up as well.
To help get over that "r" rolling thing, just say the words letter, better, middle...the mid consonant sound is so similar to the rolled r, it will get you over the "hump" as far as that pronunciation is concerned, which seems to be a big bugaboo for most of us anglos. When you come to a double r, just extend the sound, as if there were 3 or 4 t's in letttter.
I was functional @ work for Spanish, but I sure didn't tackle any thing serious like consents, or bad situations, I always felt that was a job for a REAL translator, even if wwe had to call AT&T.