1. If you have songs in mind, and you've already searched the site and can't find them here, send me a request and I'll get them up for you. The program I use is called GoldWave. They've got a really good free trial version (I think), but I bought it. I like it a lot...
I use an editing program where I'm able to turn the volume up on the song before I change it to a lower bitrate. Changing the song to a lower bitrate changes the quality and the song, but if I over-do it before I reduce it's bitrate, it comes out sounding a little better than normal...