Actually, I've already been able to do that with my laptop. It seems to work if you change the output from stereo to mono, and use VLC to increase the volume 127%. I've had to type my programs within classic99, but thanks for that advice!
I am actually unfamiliar with the process of using RS232. I've heard you need software in addition to TI EXTENDED BASIC, which is all I have. It would be sweet if you could redirect me to a tutorial for that!
To all who were wondering, I never knew you could simply paste code into classic99. I suppose I will be using that method to convert my TI99/4A text code into TIFILES!