Clownfish without anemones, and other newbie questions

Allright, I've been considering converting my spare 10 gallon
freshwater to a small sal****er tank, and considering what sort of fish
I would like to start with. My roomates really like "nemo fish," which
I believe are clownfish (not having ever seen "finding nemo" I'm not
sure).

From what I've read clownfish are fairly hardy, but what I haven't been
able to discern is whether or not an anemone is necessary. I searched
the newsgroup back a few years, and some posts say the clownfish will
die without a host aneome, others say they will be fine.

I don't really want to have corals/anemones in this tank, it just
sounds like an awful lot of work and specialized equipment. So if
clownfish desperately need them, I'll have to pick a different fish to
start with.
I'm also slightly confused by names, is there another fish that looks
similar to a clownfish but has a different name? or is there an
alternative term for them? I was in the LFS recently, and saw a fish
that looked like a clownfish to me, but was less than an inch long, and
labeled as something else (can't remember what though).

It'll be at least a month before I really start setting it up, so I
have lots of time to research. I've been going through the old usenet
archives (hooray for google archiving) and a few websites for research,
but any specific advice for my setup is welcome

I currently have a 10 gallon tank (cycled) with an undergravel and
Hang-on-back style filter. I think I will use crushed coral as a
substrate, because I already have a *ton* of it (I use it to maintain
the pH in my freshwater tank). I'm already quite familiar with the UGF
debate, but are there any extra caveats for sal****er tanks? I'm not
intensely attatched to it (its practically a religious argument for
some folks) but I did find that my water parameters were a lot more
stable after installing it.

I'm also trying to get a feel for how much this would cost. I have a
feeling I can't afford an amazing ideal setup, but I would like my tank
to be sufficient.

From my understanding I need to add live rock and a protien skimmer to
my setup, and pick up a hydrometer to measure the salinity. I already
have test kits. I also have a heater for the tank, and a ridiculous
number of air pumps ( i swear they breed). So I should be able to
convert my setup to SW for about $100-$150?

The other thing I haven't seen is the frequency/quantity of water
changes. I'm used to doing 30% weekly changes on my 40gallong
freshwater tank.

This ended up a ridiculously long post! My main concern though is the
clownfish question, I'm sure I'll dig up answers to the rest of these
as I do my research.