I would like to purchase a domain name and hosting service.  I have
several requirements for this however, and I'm not sure how to
evaluate possible hosts.

First, I would like to run a content management system on the website.
 I want to run Joomla, http://www.joomla.org (formerly Mambo).  I also
want to be able to run things like RPI generator,
http://www.last.fm/group/Image%2BSignatures%2BGroup/forum/19192/_/52206
(from last.fm).  I want to be able to do most anything on my website. 
I don't want many limits.  The problem is, I don't understand what is
required to make all of these things work.

I have another requirement - when someone looks up the whois info for
my domain, I don't want my information visible at all - even as the
owner of the domain.  I want my webhosts info (or perhaps the
registrar?) to be there.

I don't know how to find all of this.  Like I said, I want to learn,
but I need something to learn on, and I want it to be good.  One host
I have looked at is http://www.ipowerweb.com, and they seem good to me
but I am open to anything.

The privacy issue is big with me - I don't want the whois info to have
my personal address or anything.  I also obviously want a hosting plan
that is priced well with a lot of space and transfer.

If you think you can help me out with finding a host and everything,
thanks!  Please ask if you need clarification or anything!

hi kevin,

I can answer the first question. You can host Joomla with the following 

http://www.squarebrothers.com

they are the cheap and best i have ever seen with most of features you
have asked for.

Quick guidance:

DOMAIN:
Sign up for a domain at a place like godaddy.com , they have some the
best prices. [Sign up for the domain only with no bells or whistles
EXCEPT for the privacy feature which will be some extra costs but will
hide your personal information from the WHOIS records.

WEBHOSTING:
There is no best host out there but there are many that come close. 
For full support and features and price,,, overal some of the best are
http://www.hostgator.com, http://www.midphase.com and
http://www.addaction.net.  You can better research web hosts at top
webhosting resource website on the internet,
http://www.webhostingtalk.com or use their request feature
http://www.webhostingtalk.com/request.php to get offers specific to
your inquiry.

Once you sign up with a webhost they will provide you with "DNS"
server names (nameservers).  Then you would log into your domain admin
section at godaddy.com for example and punch in your new DNS
nameservers.  Within a day or less your new domain name will be point
to your webspace with your new webhost and you can start to upload
your site or configure your CMS.
[note: many webhosts will offer a free domain with their hosting
packages, you can also go this route and they generally will configure
the nameservers for you]

CMS:
Mambo was ok but the learning curve is tough, you may also want to
explore www.subdreamer.com