How do I add addon domains (I have the 9 extra free ones).. Is it $.99 a month or a year?

You have 9 without any fees.

A slight clerification I think is in order. You have the ability to add 9 additional domains with no additional fee, however you do need to register these 9 (through Hostony I believe they charge 14.95 for each per year)

Niakie: Thanks, you're right.

One free domain registration or transfer is included with any our package. If you want to host more domains with your account you should register them with another domain registar or with us for $14.85 per year

I have another question regarding Addon domains. I'm currently obtaining a domain name from a squatter, and would like to have it pointed to a subdirectory of my domain hosted at Hostony. I can point the namespace records to my Hostony NS servers.

Does my Profi account support Addon domains? If so, is it the case that all I have to do is set it up with "Addon Domain Name Maintenance" in the cPanel?

Or do I also have to make Hostony the registrar for the domain name, and pay for the transfer?

Profi package does not include addon domains.

You are not forced to transfer your domain to Hostony or register name with us only. You can do it th any accredited domain registrar and set up our name servers for the domain with them