There is a great Audio Recording and Editing Software That is Free and can be downloaded at the following link

Audacity

Link To Audacity

LAME is MP3 Decoder

Link To LAME MP3

If you want to export your edited audio out of Audacity in a MP3 format you will need to download the LAME MP3 Decoder

Below are some screen shots from Audacity which show some of it's features

An Eleven Video Tutorial for Audacity is Available by Clicking the Button on Your Right

All Main Functions Labeled.

Edit Menu Bar.

View Menu Bar.

Transport Menu Bar.

Track Menu Bar.

Generate Menu Bar.

Effect Menu Bar. There are a lot of Effects and Corrections that can be applied to the Audio for improved quality.

The Noise Reduction Tool is great for eliminating unwanted hiss and background noise.

The Envelope Tool allows you to adjust volume anywhere in the track. This is very useful for fade out and fade it.

The Equalization Tool allows you to adjust Bass and Trebel.

An Eleven Video Tutorial for Audacity is Available by Clicking the Button on Your Right

This is the bottom slider area. You can edit this text and also insert any element here. This is a good place if you want to put an opt-in form or a scarcity countdown.