I actually have mixed my own music and i used Adobe Premiere for it. The main one i used it for was for my demo reel. I took a track from the video game soundtrack to Quake and i also to a track from the soundtrack to the movie 28 Days Later and messed around with it to make it my own music. If you wanna see what i'm talking about, click on my link below that has my demo reel posted.
So would i be able to take all the soundtracks from reservoir dogs and put my own in there place?
In Premiere, once you have the movie in the program, the movie will be divided up into 2 different things. Just the movie itself and then the audio itself. And with the audio you can splice it and cut it up and highlight certain segmants and delete them. You can also manipulate the audio and even merge the audio, overlap them and play them back to see how you like how the audio sounds. And as far as finding a cheap version of the program, there are cheaper ones going around.
One last question, if i put a song in the place of another and while that other song was playing it had actors dialogue, would the song i put in cancel out the dialogue aswell as the original soundtrack?
Yes. I believe you can. You can practically do anything within the program dealing with audio and video. Once you look into the program and mess around with it, you will know it in the back of your head. It will become second nature to you. It really isn't that hard of a program to use. Once you know how to use it, it actually becomes fun just to try out different things with the audio.