2 Free Download Manager Software

I had tried use some free download manager softwares and I see that two following softwares is good

* Orbit:
I am really impressed about this software, it have functions which I need as get video links and increase download speed. It is very light and regular updated.
You need close Firefox or IE windows before installing Orbit and choose some following options:

After you had installed Orbit, you go to music websites (by Firefox or IE browser), there will be a "GetIt" button, you can click it and download every video or music links.

If you want to increase more download speed, you go to Tool --> Preferences --> ...

Besides, Orbit can notify updates in download programs list, you can edit this fuction in Software Update (Preferences).
You can find another guide in here

* Downthemall:
It is a add-on for Firefox, I'm sure it's a good download manager software.
You can increase more download speed, you go to Tools Menu in Fireofox --> Add-ons --> choose "Downthemall Add-on" and Click "Options"

* Another free download manager software:
Gigaget
Flashget

Enjoy your time