If you are going to use BT5 as your OS, make sure you create a regular user account. BT5 is designed as a pen testing OS and not really meant to be an "everyday use" OS (however it can be I guess) but the default user is the root user. Big security no no if you are running as root all the time.
Anyway to answer your question, you can download skype here: skype download
and select the ubuntu version from the drop down either 32 or 64 bit depending on what your running. The skype software should take care of your camera setup. (I have not tried the new skype 2.2 beta, however support on linux is not near as good as other OS's so you may still have some trouble)