I know Drew has had some experience with the Spanish Pimsleur program, so you might ask him what he thought of it. I got the impression that he was very impressed.
Shardian, I have no idea what your contact with people who speak Spanish will be, but the Pimsleur program worked/works quite well for my particular situation, I believe.
I work with Spanish-speaking people all day long. There generally is one person who speaks English passably, and perhaps a handful who can manage a few job-related words/phrases.
The Pimsleur CD's jam a ton of vocab down your throat through sheer repetition, although I liked the way they changed up the usage of the words - meaning you weren't always repeating "Where is my dog?", but you'd get several different sentences with "dog" in them - "What is your dog's name?", "Does Mary have a dog?", "Please give the dog a bath", etc. You get the same words over and over, but you only realize this because they group certain words in chunks. Over time, you will use some of the basics you've learned less and less (simply because there's SO much vocab that you could easily spend a CD's worth of time repeating everything you learned up to that point and nothing else!), but as with your native language, you'll find yourself using common words quite often.
Once the few Spanish-speaking people I regularly dealt with found out about the Pimsleur CD's I was listening to, they made it a point to help me with pronunciation (although they felt Pimsleur was pretty darned good at that aspect and how they taught it) and to let me know when something may or may not be useful. Usted, for example, was explained to me about when and/or why it might be used, and why it is more commonly dropped in casual conversation.
As far as becoming conversational, I felt Pimsleur gave ideas and concepts about stringing together sentences, but was lacking a bit in that area, although I can't even imagine how a CD or video course would go about trying to teach that concept in the limited amount of space these types of courses typically cover. Being in the situation I was in, I haven't ever taken a single Spanish class (not even in high school), and have simply learned Spanish over time - reading the boxes of products I dealt with at a restaurant and having the Spanish-speaking people correct me or help me remember the name of something, or picking something up and asking what it's called and trying to remember it, etc, and then adding the Pimsleur CD's....I'm still not completely conversational, but I can at least
understand what's going on in a conversation now, whereas before I went through the CD's, I only caught bits and pieces of a conversation.
There's 3 programs - beginner, intermediate, and advanced. I hit the beginner program hard - probably listened to it 8+ times and followed everything to a "T". The intermediate, I've listened to 3 times and will go through it again before I make the move to the advanced set, which I've never listened to yet.
That's my experience and the background behind what and how it's worked for me. My guess is that if all you will be doing is listening to the CD's and trying to pick up the language and hoping to run across a few Spanish-speaking people to test out or see if you can understand them, no course will teach you as well as using and testing yourself by being around Spanish-speaking people in addition to whatever other method you wish to try. You've just got no one to practice with other than the voice on the CD. If your situation is similar to mine, I wholeheartedly recommend the Pimsleur series.