Brutally honest?
The quality you are working with is rather low. It will work well for figuring out the recording process and getting used to whatever recording software you are using, but once to get rolling with the whole recording process you will outgrow both really quickly.
The soundblaster stuff is great for gaming and listening to MP3's and Cds on your computer, but it was never designed for quality music recording. It sounds good for what it is, but it
isn't a quality audio recording device.
A standard, low cost mic that IS a great recording mic is the Shure Sm57. Even though it is *cheap* for professional class mic ($80 or so) its a mic that you will keep and use forever. It rocks, and its a great mic to start with.
Since you have a SB card, I'm going to recommend that you get a different audio interface at the same time you get your preamp. The reason for this is even if you get a good preamp, your soundblaster card is *still* going to limit the sound quality. Here's a couple options:
http://www.midiman.net/products/m-audio/mobilepre.php
USB Mobile Pre: 2 ins and outs, phantom power (which you'll want sooner than later for using higher quality vocal mics) and through a USB port it goes directly into your computer. List: $175
Pros: Simple to set up, fairly cheap.
Cons: Limited to 16 bit operation (24 bit is better), will be useless when you decide to upgrade.
http://www.midiman.net/products/m-audio/duo.php
USB Duo: 2 ins and outs again, but much higher quality. Phantom power. Stand-alone mode lets you use it as just a preamp. List: $350
Pros: You use it for a long time, even if you upgrade. Simple to set up. Up to 24bit / 96Khz recording.
Cons: More expensive.
If you are more serious about a longer term process of upgrading your recording equipment (which must of us end up doing), go ahead and just get a decent preamp and use your SB card for now. Then save up and buy a REAL posumer soundcard when the time comes. It wouldn't be that much more expensive. In that case, the Audio Buddy and the DMP3 are great choices.
http://www.midiman.net/products/m-audio/audibudy.php
http://www.midiman.net/products/m-audio/dmp3.php
(I know these are all from the same company- I just don't know much about the other options that are out there. There are other options- check
www.musiciansfriend.com, www.music123.com, and
www.8thstreet.com to see what comes up when you search for "Preamp")
Also, all the prices I mentioned are manufacturer's list. Street price should be lower.
Enjoy the hunt!
Chris