A lot of this can depend on post processing as you don't take "vivid" images, so much as you "make" them. I would also submit that you need to shoot in raw, as this captures the most information in your "digital file". Also make sure that you don't blow out the highlights and over expose the shadows. Someone who really knows their way around software such as Photoshop, or Lightroom, particularly when combined with plugins such as Nik's Color Efex 4, on1's Perfect Photo Suite, etc. can probably produce some pretty vivid colours. Hope this helps.
Do you have any links to the kind of effects that you are looking for?
I highly recommend a Circular Polarizer. The best ones I've seen are B+W and Heliopan. There's also a new filter brand that came out with these really smooth light weight CPLs this year at CES. They are called Taste Filters. For filters you should always get the best though, because everything else is going to be a burden on image quality.