Chain / Sprocket Cleaning

I would like to remove my chain to clean it properly since there is a lot of
build up of dirt and grime. I am pretty sure the chain is a Shimano chain
and I have read that you need special tools to remove it.

Is there a single rivet that needs to be removed or does every link along
the chain use a rivet which can be removed? The problem is my chain is so
dirty I cannot see a thing.

How much does the tool cost to remove the rivet? Are master links which
allow easy chain removal just as strong as rivets?

Thanks in advance.

Photos of the chain, etc:
http://users.bigpond.net.au/sk/mtb1.jpg
http://users.bigpond.net.au/sk/chain1.jpg
http://users.bigpond.net.au/sk/chain2.jpg
http://users.bigpond.net.au/sk/chain3.jpg