I bought a tape deck with RCA out. I bought a converter to plug into my audio in to my computer. Once I do this and play the tape can I go directly into Vegas 3.0 or do have to buy one of those audio capture programs?
Nothing else is necessary. Simply add a new audio track, arm it for recording, and click the record button. Make sure you use the Line In, and not the Microphone input. You may need to open up the sound card's mixing control panel to select Line In as your input and adjust the volume level.
Hmmm. By converter, are you referring to a cable/adapter to connect the RCA outs to the stereo 1/8" line in on the sound card? All you need is something passive. You don't need any sort of electronic device to do this.