New to it all!

How old are your chicks? How did one disappear?  As far as I know you cannot tell if the egg is fertile or not until it has been in the incubator for a few days. You have to wait for your girls to go broody and then they will sit on the eggs. The kind of chickens you have influences how often they go broody(silkies tend to be very broody)
I do not try to hatch eggs that are older than five days, but I think they last about seven days. Do not refrigerate eggs you want to hatch. I have never hatched eggs under a broody hen before as I always use an incubator. The one time I tried it I ended up taking the eggs away just before they hatched and placing them in the incubator. If your roo is a chick the eggs probably are not fertile yet. 

This is a good starter incubator:
http://www.amazon.com/9200-1602b-Still-Air-Incubator/dp/B001CCZ8W0/ref=sr_1_1?ie=UTF8&qid=1309676014&sr=8-1

BTW

    from California

You can break an egg open to check fertility. The will be a bull's eye on the yolk.

Most try to set by 5-7 days. Some will wait longer, but the eggs need to be kept cool, so they don't start to develop. Some have even had 3 week old eggs hatch, but the fresher the better.

Several of us have hatched eggs we kept in the fridge as well as fertile eggs bought at grocery stores like Safeway and Trader Joe's. Doesn't always woork, but it's been done.

If you're looking for something fun to do, try the learning section and build your own incubator. You can usually do it for under $20 for a cheapie styro ice chest bator.

Read the posts and learning sections on this site. There's so much here to help you.

Ask questions. You now have access to some of the best chicken people around, so don't be shy.

If they don't get incubated they don't have chicks. Period. They are like any other egg. Nothing happens until the are set and the heating period starts and takes 21 days for a chick to hatch. But you don't have to worry about eating a chick. LOL That's always so funny to me. Sorry.
Your roo is plenty old enough to be fertile. Most of my younger boys are about 6 months old and they know what their doing. They don't like to just practice. LOL

A big HOWDY from Oregon!

They you'll fit right in. Some of my favorite members are from Australia!

Okay if he is 12mo then he should be fertile, but you said he just started crowing? Mine usually start around 3-6mo depending on the breed  I have raised lots of chicks over the last ten years or so, but I have only been keeping full grown chickens for three years so I do not know exactly when they become fertile.  You wont find any dead chicks so long as the eggs have not been sat on I collect mine when I go out in the morning to feed them and then I take a quick look at night for any late ones.  Like the others have said you can crack an egg open and look for a small (pin head sized) dark speck attached to the yoke.  The reason you dont refrigerate hatching eggs is because it greatly reduces your hatch rate, so it wastes good eggs.  I put the eggs I am collecting in a basket in my basement where it is about 60 degrees Fahrenheit and then pop them in the incubator when they reach five days. 
Are you sure your neighbors wont let you keep a rooster? It is so much fun to hatch your very own eggs! Of course you still can by getting  eggs from someone else 
good luck : )

A big Texas-sized